Become a Creator today!Start creating today - Share your story with the world!
Start for free
00:00:00
00:00:01
Episode 92: Make Dr. Loren Fishman Make Sense image

Episode 92: Make Dr. Loren Fishman Make Sense

S6 E92 · Movement Logic: Strong Opinions, Loosely Held
Avatar
1.1k Plays17 days ago

In this episode of the Movement Logic podcast, Laurel and Sarah dissect a recent email they received from Dr. Loren Fishman, in which he expressed frustration over their critique of his study on yoga and bone density.  In this episode, they address Fishman's email and take another look at his study, Twelve-Minute Daily Yoga Regimen Reverses Osteoporotic Bone Loss.  Laurel and Sarah's conversation explores claims made in the email, as well as Fishman's study’s methodology and findings. They compare his claims against established evidence on bone adaptation and emphasize the importance of high-load and high-impact exercise for building bone. They also highlight the need for exercise recommendations to be grounded in solid, evidence-based research—especially for women looking to prevent or reverse osteoporosis and osteopenia.

Get on the wait list for our Bone Density Course: Lift for Longevity

Follow Movement Logic on Instagram

00:00 Introduction

00:47 Personal Updates & Course Insights

14:25 Critique of Dr. Fishman's Yoga Study

52:45 Critique of Yoga's Efficacy in Bone Building

53:03 Mechanostat Theory and Bone Adaptation

55:18 Challenges in Measuring Yoga's Impact on Bones

01:06:17 Dynamic vs. Isometric Contractions in Exercise

01:10:20 Unfalsifiable Claims and Scientific Inquiry

01:15:16 Turkey Studies and Sustained vs. Intermittent Loading

01:18:14 Dynamic Strength Training vs. Impact Training

01:18:28 Cellular Accommodation and Running

01:19:00 The Importance of Rate of Loading

01:21:21 Critique of Yoga for Osteoporosis Claims

01:26:24 Red Herrings and False Comparisons

01:51:41 Concluding Thoughts

REFERENCES

Fishman’s Study

The poses in Fishman’s study

Tables of P values and more P values from Fishman’s study

Episode 79: Make Yoga U Make Sense

Episodes on the Movement Logic podcast 5, 38, 51, 53, 84, and 88 that referenced Fishman’s paper.

Episode 56 of the Yoga Research & Beyond podcast that looks at Fishman's paper.

LIFTMOR trial

LIFTMOR-M trial

Medex OP Randomized Controlled Trial

Meta-analysis on High-Load Resistance Training (HLRT)

Systematic Review on Pilates and Yoga

Bone "mass" and the "mechanostat": a proposal (Frost, 1987)

Molecular pathways mediating mechanical signaling in bone

Episode 82: Weird Science

1984 and 1985 Turkey Study

Recommended
Transcript

Introduction to Movement Logic Podcast

00:00:00
Speaker
I'm Laurel Biebersdorf, strength and conditioning coach. And I'm Dr. Sarah Court, physical therapist. With over 30 years of combined experience in fitness, movement, and physical therapy, we believe in strong opinions loosely held. Which means we're not here to hype outdated movement concepts.
00:00:15
Speaker
or to gatekeep or fearmonger strength training for women. For too long, women have been sidelined in strength training. Oh, you mean handed pink dumbbells and told to sculpt? Whatever that means, we're here to change that with tools, evidence, and ideas that center women's needs and voices.

Personal Updates and Marathon Goals

00:00:32
Speaker
Let's dive in.
00:00:47
Speaker
Welcome to season six of the Movement Logic Podcast. I'm Laurel Beaversdorf and I'm here with my co-host, Dr. Sarah Court. Sarah, what is good? How's life?
00:00:59
Speaker
Life is good. i have some very exciting personal news that is going to impact my life in a very positive way, but I can't fully talk about it yet because it's not going into effect until April and it's not yet public knowledge and I don't know who listens to this podcast.
00:01:13
Speaker
um No, I'm not pregnant. That would be like a literal miracle because I'm postmenopausal. i thought you were going to say because I'm a virgin. Yes, that's why. That's why.
00:01:25
Speaker
What about you? Oh, I am running, running, running up a storm. I just got a pair of carbon plated shoes, which are called super shoes, which are taking the running world by storm. No, they're lightweight um shoes that give you more return on impact so you can actually run faster. oh cool. And I am excited about that. I decided, you know, kind of like how you buy motorcycles, I decided that I'm probably to...
00:01:54
Speaker
ah much, yeah much to my husband's chagrin, probably going to become a collector of racing shoes. Cause they're just so fun. Um, you can't, you can't wear them too much though, because they're, they're not intended to be worn, uh, for regular running, but oh i see they're like just special for racing. Yes. I've got a couple of race goals coming up. I've got a 5k on Saturday. I'm trying to run sub seven minute miles for that, which is going to be very hard and it's going to hurt for about 20 minutes.
00:02:22
Speaker
And then it'll be over and hopefully I will reach my goal. If I don't reach my goal, it's all good. I'll still feel good about it. And then um my other goal is I'm going to run my first marathon at the end of May and Traverse City, the Bayshore Marathon. Looking forward to the beautiful view of Lake Michigan for that one.
00:02:39
Speaker
And i am going to try. This is ridiculous, but it's kind of like my style. I'm going to try to qualify for the Boston Marathon with my first marathon. Let's see if I can do it. I've never run a marathon. Why not try to be cute? Okay.
00:02:56
Speaker
Because I think according to some predictors that I might be able to BQ. Wait, what is BQ? Yes. Qualify for Boston. i didn't Listen, this is this is where it's actually ridiculous.
00:03:07
Speaker
I was new about the Boston Marathon, obviously. And I knew that, right, it's a big deal to run Boston. But I didn't know why. And I guess like one of the reasons it's kind of a big deal is because...
00:03:20
Speaker
you have to qualify for it or you can be ah you can be a part of a charity, right? So there's there's two ways. so Whereas a lot of other really popular marathons like the New York City Marathon, um you have to get you selected out of a lottery.
00:03:34
Speaker
But for Boston, you have to qualify. So they ah stratify it by age and gender. And I looked at the times and I was like, um my half marathon time is this, which means my marathon time could be this and so maybe I could qualify for Boston which would be kind of awesome I think given that I have not really been running regularly for even two years so I'm going to try but the thing about marathons is that i feel like there's more of a difference between a half marathon and a marathon than there is between a 5k and a half marathon just in terms of like yeah what your body has to experience so I don't have as much time um on the on the road like putting in the miles as I might
00:04:13
Speaker
need to, to perform how I want to perform for this marathon, but I'm going to fucking try. Why not? try Yeah. Why not not? Because even in the trying, right, even in the preparing for it, you're going to be getting better at it.
00:04:26
Speaker
yeah So it's just going to be like a step along the way. And maybe it's one big step and suddenly you're in the Boston marathon. Holy shit. Or maybe it's just part of the path and you get there next year. i don't know.
00:04:37
Speaker
Yeah. and I haven't even decided if I'm going to run the

Coaching and Bone Density Course Success

00:04:39
Speaker
Boston Marathon. I just want to see if I can qualify.
00:04:43
Speaker
I mean, I probably will run it, but. That's hilarious. You're like, did you? ah Yeah. You're like, you're like I qualified. So why bother doing it? Yeah. But I'm sure you can relate. Like this hobby is getting more and more expensive the more and more I get into it. Like, can can you kind of relate to that? Oh, in the in the in my motorcycle hobby addiction? Yes. When your hobby involves buying things that are multiple thousands of dollars and then having to upgrade them with other multiple thousands. Yes, suddenly it becomes a very expensive hobby. Yeah, when I when i bought my racing shoes, they're they're more expensive than regular shoes, but not as bad as you'd think.
00:05:12
Speaker
I was like, well, at least I'm not buying motorcycles like Sarah. ah Keep things in perspective. Yeah. you can And also that's always going to work as a really good argument for Nathan because- Yes, of course.
00:05:25
Speaker
It's that way. It's like, look, ah you you could have gotten stuck with somebody who's buying motorcycles and that would be way worse because then we'd have to choose between like, you know, motorcycle or feeding our child and the motorcycle would win. So- i mean, I think he is pretty relieved that I'm not into like designer bags and designer shoes for that reason.
00:05:43
Speaker
Yes. But now I think I'm making them a little nervous with my race shoe thing. I'm going to find the most expensive race shoe out there and send it to you. And be like, buy these. No, not that I'm going to buy them. I'm going to send you the link and say, here you go. I would love that. Yeah. the nation Well, this is where we have to start to get sponsorship for you.
00:06:03
Speaker
Exactly. Oh, yeah. I mean, I'm just, ah you know, someone you'd want to sponsor as an athlete. one son Why not? Why not? Everybody starts somewhere. I guess for the symbol symbolism of it. I mean, i I'm no spring chicken, but I don't know. I can think of a lot more inspiring people to want a sponsor than me.
00:06:23
Speaker
I'm going to disagree, but anyway. I'm going to sponsor myself. There you go. Movement Logic can sponsor you. Okay. We're going to make a special race shirt that has Movement Logic on it. We should. We should. We should make a shirt for for runners.
00:06:36
Speaker
Yeah, absolutely. Can I tell an unrelated story that it will definitely get cut? ah Yeah. So when I used to work in... I'm laughing because I get to edit this. Yeah. A long time ago, I used to a volunteer for a nonprofit based in South Africa. And i can't even remember what this was, but we were we were in South Africa and we had to get race.
00:06:57
Speaker
I guess some people were running a race and they were going to give the free but get sponsored and give the benefit money to this nonprofit. And so we were buying race jerseys and we went to the store and ah but big part of the story is the fact that it happened in South Africa. So me, a white woman walks in with a black man, which is already unusual to the store. a white woman behind the counter.
00:07:17
Speaker
And we're saying that we need to buy these jerseys, but there had already been a lot of conversation that they had to make, we had to make sure that we got this kind of didn't chafe your nipples. Oh yeah, that's a big deal. Yeah. Bloody nipples at the end of marathon. Yeah. And so we've got the... <unk>s like it's It's like one of those problems that men have and women don't. Right. Because women are wearing their sports bra.
00:07:35
Speaker
Okay. i'm glad I'm glad I don't have to deal with that. Finally, finally this is their problem. And so watching him talk to this white woman about bloody nipples was one of the funniest things I'd ever seen because she was trying to be real like professional and serious.
00:07:51
Speaker
And he's like, you know... And like gesturing at his nipples and going bloody nipples. And she's like, uh-huh. It was amazing. You know what I've heard solves that problem pretty well is just like athletic tape.
00:08:04
Speaker
yeah was this a can across your up Yeah. Or like a bandaid. came a bandaid Yeah. But the the sweat might make the bandaid come off, but like athletic tape is designed to be able to be sticky yeah while sweating.
00:08:16
Speaker
You should definitely cut all of that out. um Sure. This episode is already going to be so long. Just think of it as already cut. It's gone. Stuff going on in BDC, bone density course, this is the thing we're doing this season, ah is, you know, just talking about things coming up in the live classes, and this one's kind of short.
00:08:35
Speaker
But we have this exercise called the ab roller where you use a barbell, Like you would use an ab wheel, you know, those little wheels at the gym with the two handles that stick out of the side that you then roll. You're in a plank, you're on your knees, or you're in quadruped, really. You're on you're um on your knees and you roll that forward and your arms come into that overhead position and you're sort of flattened out.
00:08:56
Speaker
And at the mercy of gravity. And it's super potent exercise for the core to to shoulder connection. And so we use a barbell to create that effect ah for our access one of our accessory exercises, the ab roller, as we call it.
00:09:13
Speaker
And I've been noticing some progress in the group with the ab roller where I'm starting to notice people are able to maintain that more hollow body position in their trunk rather than kind of collapsing into what would be like a cow post or keeping that kind of hollow lift of a cat spine. And then they're able to roll the barbell out even further. And I've been now adding onto that sort of layering in the nuance of this exercise to own that outstretch position and kind of pause and hold it. and Nice.
00:09:47
Speaker
And so that's been really cool to see how the exercise techniques are evolving toward greater range of motion and greater control.
00:09:59
Speaker
And that's the name of the game, right? So the whole reason that we have this coaching element as a part of the course, whether the coaching is taking place in the live classes or the coaching is taking place in the form check videos,
00:10:13
Speaker
that gets shared in the chat and our Facebook group. The ah purpose of it is really to create this process for people to go through where we, with our coaching, meet them where they are in the beginning and give the type of cues and coaching that they can digest and use at that stage. But then as they become stronger and more skilled in the movement patterns, the coaching cues change, right?
00:10:40
Speaker
So whereas before we weren't emphasizing, you know, own the position and pause for a moment, we were instead emphasizing, you know, the timing of moving that barbell forward, what joints unfold when, keeping that cat spine. Now we start to layer in this like extra...
00:10:55
Speaker
kind of like frosting on the top of the cupcake type cueing where they're just going to be able to, because they have that baseline of strength, get even stronger and even more skilled. So it's like you're you're you're not ready for everything all at once.
00:11:09
Speaker
And um sometimes when you get like a DIY program, just a PDF with video links, you get demo videos that kind of give you the kitchen sink and like tell you everything. yeah And it can be a little overwhelming because you're like, well, what's, what's important now, right? Right. What do I need to focus on now? And you don't necessarily always get that with a demo video, but when you take part in a course that's delivered in real time and everyone is kind of ah going along the same process together and there's this live component, this, the synchronous component,
00:11:42
Speaker
as well as this asynchronous component, you get what you need when you need it. yeah And I think that's one of the main reasons that number one, this course is ah so different from other courses, but also one of the main reasons we see the type of progress we see, which is very, very exciting.
00:11:58
Speaker
Yeah, definitely. we're We're really entering, we're into month five now of our six-month course, and we're really entering into that nuanced period where we're fine-tuning things. It's no longer, a wait, where do I put my hands and where is the bar supposed to be? But it's now we're getting into some of that more advanced detail. And it's really, i mean, it's so exciting. its so This is, I think these two months are my favorite of the course because this is where they're all just starting to like take off.
00:12:22
Speaker
Yeah. And like not need us as much. Yeah. And I love it. That's, that's our entire goal. So it's really satisfying. Yeah. The breakthroughs start to happen at month three and four. And then the like realization of the changes that have taken place and just how profound they've been. Yeah.
00:12:40
Speaker
start to come month five and six. And

Critique of Dr. Fishman's Yoga Research

00:12:42
Speaker
that's when we get all the like gushing Facebook messages. So in class yesterday, we're at the end of the class and one of the participants unmuted herself and she goes, Sarah, I need to tell you something.
00:12:52
Speaker
And it was kind of very serious. And I was like, oh God, oh no. I like went into like panic mode. Like what? She hurt herself, something happened, something's broken. and I'm like, any news is always going to be bad news. And she goes, I'm getting stronger.
00:13:05
Speaker
Like, like, like, like it's a secret. It was the sweetest thing. And I was like, that's awesome. And she said, I don't notice it so much in the class, but I'm noticing it in my life. Things that I carry are not as hard.
00:13:17
Speaker
She said, I am a snowboarder. And it's in the past, it's been when there's a lot of powder, it's really hard to stay on top of the powder, but now it's not so hard anymore. And was just like high-fiving in the background of like cheering. It's so, it's so exciting. That's the thing.
00:13:31
Speaker
Right. And then, and then after class, I walked out, my mom was like, I realized i can deadlift a 35 pound bar. I can carry both bags of groceries in at the same time. And I was like, yeah, you sure can. yeah So making these connections to real life as well and noticing how it's impacting their lives in real time is just also my favorite.
00:13:48
Speaker
Oh my gosh. yeah It's why I do what I do. Yeah, absolutely. Sarah, any new reviews on the podcast? Have you been keeping tabs on that? I know you're always checking. Yes. In fact, we got a review of episode 79, which was called Make Yoga You Make Sense.
00:14:05
Speaker
And the reviewer called it an upbeat and talky hatchet job and a negative infomercial. um just kidding. This was not a podcast review. This was in an email that we received just out of the blue. Yep.
00:14:18
Speaker
Dr. Lauren Fishman emailed us to express his disappointment with our critique of his work. And in this episode, we plan to share the contents of his email, look at some of the claims he makes, and discuss the research he cites to support his arguments.
00:14:34
Speaker
But just as important as what he says is how he says it. And we'll be taking a close look at that too. Because the way an argument is framed can make it seem more convincing than it actually is.
00:14:47
Speaker
And while these techniques aren't always intentional, they have a real effect. They can make it harder to separate what's actually supported by research from what's just persuasive language. Sarah and I feel this is especially important now, given what has taken place in our country at a time when misinformation is spreading faster than ever, when fact checking is being scaled back, when expertise is being dismissed, and scientific consensus is treated as just another opinion.
00:15:13
Speaker
It's more important than ever to exercise our critical thinking skills. So our goal in this episode isn't just to fact check Dr. Fishman's claims about yoga and bone health. It's to demonstrate ways to recognize flawed reasoning and misleading rhetoric wherever it shows up.
00:15:29
Speaker
Yeah, we already had a whole season planned out that was going to spend several episodes separating fact from fiction around bone density. As you have already heard, we have interviewed Professor Belinda Beck, who was one of the lead investigators of the Liftmore trial, which showed that osteoporotic post-menopausal women could not only lift weights and perform impact training without injury, but that by doing so, they improved their bone density.
00:15:52
Speaker
We've also recorded an episode that's coming up where we take a deep dive into the study by Sinaki et al. that convinced movement teachers that all people with osteoporosis, regardless of severity, need to avoid spinal flexion. And then we also have a whole episode coming up about what we like to call bone density grifters, which are people and businesses who go hard in the paint to try and convince people that their modality or their training is all you need for osteoporosis when that modality emits any meaningful load or impact that could really move the needle on bone density.
00:16:24
Speaker
So when we heard from Dr. Fishman, we knew that we wanted to include this exchange in the season, as it is an opportunity for us to hopefully, once and for all, although who can say, go through his assertions around his research and clarify what meaningful impact, if any, yoga has on bone density.
00:16:42
Speaker
Okay. So if you're listening and you're like, who the heck is Dr. Fishman? If you don't know the backstory, story right? If you're like everyone who watched the Superbowl halftime show and said, why is Kendrick Lamar so mad at Drake? That would be me. So who's Kendrick Lamar? Now, there we go. And who's Drake? Yeah.
00:16:57
Speaker
ah So if that's you, here's a quick, not not not going to recap the Kendrick Lamar Drake beef. You can look that up on Google. It's very interesting, but we're going to recap the sort of who is Dr. Fishman. So he is a medical doctor. He was a researcher on a paper entitled 12-Minute Daily Yoga Regimen Reverses Osteoporotic Bone Loss Now, the title is misleading, the contents are confusing, and ultimately the study does not prove what the title claims.
00:17:24
Speaker
But what happened was the yoga world got very excited that yoga is once more the best for something. And I think this is a ah ah characteristic unique in a way to the yoga community where we want yoga to be the fix for everything, right? And so in this case, that it was the best for osteoporosis.
00:17:38
Speaker
And then Yoga U Online, which is a company that makes educational ah videos and continuing education content for yoga teachers. It's one of the biggest companies that jumped on this bandwagon and had several articles and courses based around this research.
00:17:53
Speaker
And you may have heard our takedown of them in episode 79, which is the episode Dr. Fishman refers to in his communication with us. Any episode we mention in this podcast will be linked in the show notes, by the way.
00:18:03
Speaker
Yes. So several people, Laurel and i included, have now had to spend a lot of time and energy on cleanup, right? And even with our efforts, it's very hard to get the toothpaste back in the tube, which means a lot of people have learned that yoga is good for osteoporosis, when in fact, if it has any effect, it is extremely low and slow and ultimately far from the best option for improving your bone mineral density.
00:18:29
Speaker
Okay, so let's get into the email that he sent us and the subsequent conversation that took place. We're going to go through the contents kind of piece by piece and break it down for you. All right. So he opens with hello to both of you from Dr. Lauren Fishman, to whom you gave an upbeat and talky hatchet job in episode 79 back in September 2024.
00:18:50
Speaker
It's depressing to me that you looked at an interview to do this rather than looking at our article, 12-Minute Daily Yoga Regimen Reverses Osteoporosis, published in 2016.
00:19:02
Speaker
So Dr. Fishman seems to think that we only engaged with his research paper through a blog post interview on the Yoga You website and that we then reported on that exclusively in our episode 79, Make Yoga You Make Sense.
00:19:17
Speaker
However, in episode 79, we referenced episode 51, where we had already extensively analyzed his paper, And we've discussed his work not only in that episode, but directly or tangentially in episodes 5, 38, 51, which I mentioned, 53, 84, and 88. Again, we'll link all those episodes in the show notes.
00:19:38
Speaker
Along with episode 56 of the Yoga Research and Beyond podcast, where Jules Mitchell and Ariana Raven critique his study as, quote, complicated and underwhelming with incomplete and inconclusive data, unquote.
00:19:53
Speaker
So since the start of this podcast, we've been addressing the misinformation from Dr. Fishman's paper and his book, Yoga for Osteoporosis, which he co-wrote with Ellen Saltenstall, who is a yoga teacher.
00:20:05
Speaker
I've started reading the book, and we plan to cover that as well in a future episode, so stay tuned for that.

Analysis of Dr. Fishman's Claims and Book

00:20:12
Speaker
So Sarah, do we just love to pick on Dr. Fishman or what's our deal?
00:20:19
Speaker
Can you say more about why we keep talking about his work on this podcast? Yeah, I started thinking about that song, Why Are You So Obsessed With Me? That's why laughing.
00:20:30
Speaker
ah We're not, we're not, this is not personal. But why we keep talking about his work is that unfortunately, many companies, individuals, organizations have used this study as strong evidence that yoga can reverse osteoporosis and have written articles in AARP and in Harvard Health to name just two.
00:20:51
Speaker
There are many more. Also, Yogi U Online who developed a whole section of their Con Ed course to this concept. I know they took down some of their articles after our episode, but I looked quickly just now and they still have a course that's called Beyond Bones, The Real Keys to Fracture Prevention with Ellen Saltenstall, which this episode is not about taking that apart, but in essence, it's saying it's more important to work on balance.
00:21:15
Speaker
So we just are trying to put the facts out there. That's honestly all we're doing. In Yoga for Osteoporosis, Dr. Fishman and Ellen Saltenstall's book, they list various exercises, including weightlifting, to compare against yoga.
00:21:30
Speaker
The reason I'm telling you about Yoga for Osteoporosis, the book, is that it's a big part of Dr. Fishman's work. And so I want to give you some perspective about what's in that book, because there's a strong connection between what's in that book and what he looks at in his paper. In fact, he uses his paper to support a lot of the claims he makes in his book. But just for some background as well about why Sarah and I, who promote heavy strength training for bone strength as well as many other benefits, are looking at Dr. Fishman's work specifically in his claims
00:22:03
Speaker
about yoga for bone health. OK, so in his book, he is comparing various exercise formats, including weightlifting and comparing them against yoga. However, in the book, when he does this, he is basically undermining weightlifting by stating that while it can build strength, he claims that it doesn't improve range of motion.
00:22:26
Speaker
OK, in contrast to yoga, which I guess he's suggesting does. This is actually an incorrect claim. Strength training does improve range of motion. He says that it doesn't improve balance in the book. This is also incorrect.
00:22:37
Speaker
One of the best ways to improve your balance is to get stronger, especially lower body strength training. He says that it doesn't improve your flexibility, which is the same thing as range of motion. Again, also incorrect.
00:22:47
Speaker
They also write in this book that Strength training carries risks like low back pain and shoulder dislocations. Again, this is wrong. This is misinformation. Weightlifting is extremely safe.
00:23:00
Speaker
And not only that, but strength as a capacity is protective against injury. Yeah. The shoulder dislocation seems like it's out of nowhere. Like it's a random one to pick. Yeah.
00:23:10
Speaker
So they present all of these exercise formats that they list off, including Tai Chi and Alexander technique, if you could even call that exercise. I think that's a bit of a stretch.
00:23:21
Speaker
and And various others. They present them alongside yoga as all having drawbacks, unlike yoga, which they position as the superior option for building bone. And it's in this part of the book where the bias is just so glaring.
00:23:36
Speaker
Here, I'll take a direct quote from the book. So let me just give you a little context. This is a quote talking about the potential benefits of weight training and then also listing some of the drawbacks. So here's the quote. Weightlifting surely does produce the forces. Weights are easy to obtain and use at home.
00:23:52
Speaker
No question about building strength either. The disadvantages are that lifting weights does not improve range of motion, do much for balance, or involve much stretching through which cartilage thrives.
00:24:05
Speaker
Strength training produces stretching too. It's called eccentric muscle contraction. up So I'll go on with the quote. Also, weightlifting can give rise to a number of orthopedic and disc-related injuries from low back pain to shoulder dislocation. So then the book goes on to say, here's the quote.
00:24:20
Speaker
After a short inspection of yoga, many conclude It is the logical best choice to prevent and treat osteoporosis. Many conclude, that's like saying people say.
00:24:33
Speaker
First of all, it's not even remotely the logical best choice. And then who are these many? right The scientific community agrees that weightlifting and impact training are the logical best choice.
00:24:44
Speaker
Throughout the book, Fishman and Saltonstall speculate on yoga's ability to build bone. They often use research that doesn't specifically examine yoga or even exercise for bone building.
00:24:54
Speaker
Much of the research they cite is only loosely related, making it insufficient for drawing the conclusions that they draw about yoga's effectiveness in promoting bone health. It's conjecture.
00:25:06
Speaker
I wonder, though, how many female yoga students have read this book, students who are approaching perimenopause or menopause, and who, having read this part of the book, have become turned off by strength training and actually osteogenic exercise because it's dangerous, according to this medical doctor who is telling them that yoga will be enough when that is likely what these readers wanted to hear anyway.
00:25:33
Speaker
So back to his email. So he refers to our episode 79, Make Yoga, You Make Sense, as a hatchet job. And was like, what's the definition of a hatchet job? i was curious. So it is defined as a forceful or malicious verbal attack.
00:25:48
Speaker
So was this episode forceful? Probably. But malicious? Absolutely not. We have no bone to pick, sorry for the terrible pun, with Fishman personally. And if we give him the benefit of the doubt, he may not have meant that we were being malicious.
00:26:01
Speaker
I generally think of a hatchet job as something where you come in and just aggressively chop something to pieces, and as a result, you're missing the important details that you would have seen had you used a more delicate tool.
00:26:13
Speaker
So he is suggesting that we didn't look thoroughly enough at the research before we shredded it, ah which is just untrue because we've both looked at it a lot. Yeah. I also picked up on the word, quote, talky.
00:26:25
Speaker
So we are podcasting. is Spoken word. So there will be talking. Or in my mind, was he insinuating that we, quote, talk a lot? As in, quote, women talk a lot.
00:26:39
Speaker
I'm having a hard time imagining him using that word if the hosts were men, frankly. That's usually what I do when I'm wondering if there's something that's been said in a gendered way toward me is I just try to imagine it being said to men.
00:26:52
Speaker
And if I have a hard time imagining that, I start to wonder. I am sensitive, like most women, to misogynistic tropes like this. Yes. And so my hackles went up a bit in reading that word talky.
00:27:03
Speaker
But to be fair, I don't actually know what he meant in using this term, so I'll benefit of the doubt it. Talky can also mean overly informal or lacking in substance. And I would disagree with that analysis as well.
00:27:15
Speaker
Our episodes are critical, yes, but they are also substantive and evidence-based. Anyway, interpreting his use of the word talky as lacking in substance rather than as a way to undermine our credibility with a gendered interpretation of our work, that would certainly be the more generous interpretation of what he meant with that word choice.
00:27:34
Speaker
He also called us upbeat. i think that's true. Yeah, I think so too. I think we're pretty upbeat. um But if we zoom out, calling our episode a, quote, talky hatchet job, albeit an upbeat one,
00:27:48
Speaker
is a choice, and I think we need to spotlight this choice here. Because right out of the gate, rather than engaging with the substance of our critique, he frames our episode as a talky hatchet job, which strongly appeals to emotion.
00:28:03
Speaker
If we're truly interested in critical thinking, and we've decided that facts and evidence are important, then we must also start to pay attention to the underlying agenda in people's words, which may not be what's explicitly said, but rather what's implied.
00:28:19
Speaker
Emotional appeals like Fishman's are agenda-laden. Word choices like these can serve to connect with people's values, their fears, desires, and identities.
00:28:30
Speaker
And in doing this, they can make an argument personal or make it feel more personally relevant rather than just intellectual or intellectually compelling. And as we are becoming increasingly aware of in this country, people are more likely to be swayed by arguments that evoke feelings rather than data and facts.
00:28:50
Speaker
So, it's a good idea to start to listen for this type of agenda-laden emotional rhetoric. When is it used and why? What does the speaker want you to believe?
00:29:02
Speaker
And how are they appealing to your emotions to get you there? Yes, he also said he found it depressing, which I'm sure it is for him. But neither Laurel nor i are emotional pack mules, so we do not feel the need to take care of his depression for him.
00:29:17
Speaker
With that said, our reporting on Fishman's research study on 12 minutes of daily yoga for osteoporosis concerns two key issues. Number one is the correct interpretation of the data and the facts on bone building and how that then impacts people's choices of how to address their osteoporosis and by what methodology.
00:29:36
Speaker
And then also how the misinterpretation to misinformation pipeline works effectively. or doesn't work rather, how misinterpretation of the evidence leads to the spread of misinformation around exercise and bone building.

Methodological Flaws in Yoga Study

00:29:51
Speaker
And in this instance, the overplaying of yoga's benefits for bone density, which we feel Fishman's study is largely responsible for. I like that phrase, misinterpretation to misinformation pipeline. That's a really good one.
00:30:04
Speaker
Thank you. ah In our opinion, this has done considerable harm. And we spotlight this on this podcast, sometimes quite forcefully. Are we always completely emotionless while doing so? No, but we do stick to the evidence.
00:30:17
Speaker
Fishman here is going to list out the credentials of researchers involved in his study. So he writes, Yi Shui Liu was a PhD doing a postdoc at Rockefeller. Bernard Rosner is a Harvard professor and the chief biostatician at Brigham and Women's and the deaconess.
00:30:34
Speaker
And Gregory Chang is an MD, PhD at NYU who has the seven Tesla research um MRI that informed us of the trabecular strength of 30 of our patients.
00:30:45
Speaker
Okay, so I found it interesting that Dr. Fishman took the time to list out all the credentials of the researchers involved in his study, Harvard, Rockefeller, and NYU. We didn't ask, and it's something you can easily search.
00:30:56
Speaker
And while these are big sounding names and no one is disputing that they are highly accomplished professionals, I think we have to wonder. On the one hand, it's fair to mention their expertise because qualifications definitely matter in research.
00:31:10
Speaker
But on the other hand, this can also function as a subtle appeal to authority, which is another rhetorical device where the focus shifts from, for example, what the study actually found to who conducted it.
00:31:22
Speaker
And here's the problem with that. Even highly credentialed researchers can produce flawed studies. Science isn't about who has the most impressive resume. It's about whether the methods and conclusions of the study hold up to scrutiny.
00:31:37
Speaker
So rather than addressing specific concerns about his study's methodology, he directs our attention to the prestige of the people involved in it. And this can discourage critical analysis.
00:31:49
Speaker
No amount of credentials, though, can override the actual limitations of the study, which the paper itself even acknowledges. Yeah. So here's how Dr. Fishman summarized the results of his study in his email to us. And this is important to note because he omits a lot of important information.
00:32:07
Speaker
Okay, so this is a quote from Dr. Fishman. The average age of the 741 patients in the study was 68.3. Over 80% them had osteoporosis osteopenia. over eighty percent of them had osteoporosis or osteopenia We measured the change in their bone mineral density in the two or more years before starting our 12 pose regimen, and then in the two years in which they did yoga.
00:32:27
Speaker
There were significant improvements in the spine and femoral neck And he quotes a statistical value called the probability value, which is indicated by the letter P. So he says P is less than 0.001.
00:32:39
Speaker
Now, whether you understand statistics or not, I want you to put a pin in this that he quoted the P value alone. And this is going to come under the heading of misinterpretation leading to misinformation.
00:32:49
Speaker
And I'm going to talk a little bit more about that later on. And then he said, quote, this was a study that took us eight years to complete. And I'm Sorry You Didn't Take a Look at It, or the book Yoga for Osteoporosis, published by W. Norton by Ellen and me.
00:33:03
Speaker
Okay, so before I summarize the study again, want to note that he again uses this appeal to a emotion with I'm sorry you didn't take a look at it. You know, my interpretation of this is that he's trying to dismiss what we're saying by saying we didn't do our research, pun intended.
00:33:17
Speaker
But as we said earlier, we have spent a lot of time reading about and talking about his study. Yeah, I had actually already bought his book. And I had done that months ago. I was intending to read it. But I did speed up the process of reading it before recording this episode. And despite how difficult it has been to frankly, stomach some of the misinformation I'm encountering in the book.
00:33:38
Speaker
We've become very familiar with his work and his message about yoga for osteoporosis because we have to. We're interested in correcting this misinformation. In order to do that, we have to understand what is being said. We've really had no choice but to deep dive into his work. So reluctantly, we have become extremely familiar with his work. Yeah.
00:34:01
Speaker
And at first he told us to read the book, but then after Laurel responded that she had the book, he replied that a new edition is coming out in March, so don't bother to read it, which I'm just confused. Yeah, I mean, I'm really looking forward to getting the new edition.
00:34:15
Speaker
I want to see if there have been changes made. I'm really interested to see what has been changed. And that's something we'll just have to talk about once it comes out. We'll do an episode about both editions. All right, but back to his study, 12-Minute Daily Yoga Regimen Reverses Osteoporotic Bone Loss.
00:34:30
Speaker
One thing I want to say up top is that there are a lot of sentences in this write-up that are difficult to understand. I'm going to pick out a few examples as I'm talking about this study. And we'll have a link to this. Literally everything that we mentioned will be linked in the show notes.
00:34:43
Speaker
So the study is comparing the relative safety and efficacy of yoga versus medication for bone density improvement. So the methodology was they chose 12 yoga poses and they made a DVD of how to perform these poses.
00:34:54
Speaker
And then that DVD was distributed to people who signed up at Dr. Fishman's website, sciatica.org. And there's a link of a picture of all of the poses that we're going to put in the show notes as well.
00:35:05
Speaker
But just to note, if you're not a familiar with yoga, the first five poses are standing poses, meaning you're weight bearing through your feet. The remainder are either seated or lying down. And then the final pose is Shavasana, which is lying on the ground with no muscle activity at all. It's traditionally included at the end of a yoga asana practice.
00:35:22
Speaker
So in order to be included in this study, apart from signing up, you also had to have had a DEXA scan within six months of starting the study. And if your DEXA scan showed osteoporosis, then they also had to go through some lab tests to rule in or rule out the participant based on any other possible confounding health factors.
00:35:41
Speaker
And then the exclusion criteria was, you know, any abnormal lab results, as mentioned above, or any other types of bone diseases. The participants agreed to do the DVD daily for two years, at which point they would have another DEXA scan to see if there were any changes.
00:35:55
Speaker
And then here's this sentence, and this is a quote. agreement to continue the current medication, nutritional, and exercise regimen for the following two years." End quote. So what medication, nutritional, and advice regimen is this referring to? It is never made clear.
00:36:10
Speaker
Were participants given additional exercise guidelines like don't do any other type of exercise or make sure you meet the CDC minimum exercise guidelines? This is some just really important information that we don't know and it would be good to know.
00:36:24
Speaker
So the DVD had three versions of each pose, beginner, intermediate, and classical. Particums were allowed to progress through the levels of difficulty, self-paced, and to hold each pose for 30 seconds.
00:36:36
Speaker
Here's another sentence that does not give us enough information about what it means. Quote, bone quality measures were qualitative, end quote. I have, laural what does that mean, Laurel? Do you have any idea?
00:36:48
Speaker
um Well, if you measure something, isn't it Isn't it quantitative? I don't know. Were people given a survey about how they felt about their bone quality? I'm i'm really, I'm just as stumped as you are. Yeah. Okay. So don't know what that means.
00:37:00
Speaker
After two years, participants had a follow-up DEXA scan of their spine, femur, and hip. So let's look at the results. So
00:37:09
Speaker
stick with me. In the 10 years between 2005 2015, 741 participants joined the study. seven hundred and forty one participants joined the study 227 of them were compliant with more than every other day yoga, which I take to mean then between five to seven days a week. The initial instructions was to do it every day.
00:37:27
Speaker
So only 227 of the 741 actually did even close to that. Women were 202 of the participants, and it's not specified if this is 202 of the 227 or total 741. We know.
00:37:40
Speaker
or of the total seven hundred and forty one we don't know It then describes that many people did not submit a prior DEXA scan, another number did not submit a DEXA scan following the yoga, and another number did not enter enough information about their compliance with the yoga practice. So because of this, they took these three groups And they analyze the data separately in three different tiers based on each of these criteria. So whether you didn't do a prior DEXA, whether you didn't do a follow-up DEXA, or whether you didn't put enough information about your yoga practice.
00:38:14
Speaker
So these... were grouped into tiers of 128, 130, and 135 respectively. How this relates to the 741 or the 227 is unclear.
00:38:26
Speaker
But the point to notice here is that we have three incomplete data sets, right? The study's methods were supposed to be DEXA scan, and then you do your two years of yoga, and then you get another DEXA scan.
00:38:40
Speaker
Now it's possible that the group that reported they did yoga every day followed this formula. It's not clear from the study, but that's, if that's the case, that's only one of the three data sets that they are then analyzing.
00:38:54
Speaker
Okay. So part of the statistical analysis done here was to divide the standard deviation by the confidence interval. Okay. So just so we're all on the same page, standard deviation measures the average amount by which data points differ from the mean.
00:39:10
Speaker
indicating the spread or the variability in a set of data. And your confidence interval is a range of numbers that likely includes the true value of something you're trying to measure with a specified level of confidence. So if you have a high confidence interval, that's good. You're you're relatively very confident that the number that you're trying to ascertain is within this data set.
00:39:37
Speaker
Okay, so part of the statistical analysis done here was to divide the standard deviation by the confidence interval. Okay, bear with me. I was curious because though I am by no means a statistician, this is not a typical way to analyze data. So I looked into it and here's what I found.
00:39:55
Speaker
Dividing the standard deviation by the confidence interval can give you a rough sense of the precision of an estimate relative to variability in the data. However, this is not a standard statistical measure.
00:40:10
Speaker
And I went down a huge internet rabbit hole and almost put all of it in this episode. And Laurel was like, dude. So I came back out of it. I know a lot now about precision of an estimate relative to variability, but I'm not goingnna i'm just going to conclude it for you, which is the bottom line is that dividing the standard deviation by the confidence interval lacks a clear theoretical basis.
00:40:33
Speaker
and does not directly correspond to any widely used statistical concept. They also analyze the change per month in bone density divided by the confidence interval, and that is also not a standard measurement.
00:40:47
Speaker
It's not clear how they are estimating the monthly bone mineral density change because participants are not getting monthly DEXA scans. And, you know, even with effective...
00:40:58
Speaker
and methods that improve bone mineral density, you're not seeing a huge change month over month. The values are going to be extremely low. I wonder why they chose to do it this way.
00:41:10
Speaker
You know, this is total conjecture. But why why did they choose to do it this way? Did it have to do with how the data appeared when using a standard statistical measure? For example, let's do this atypical analysis to see if it makes our data make more sense kind of a thing.
00:41:27
Speaker
Yeah, we don't know. We're just, that's just sort of a guess, but we're just pinning that already it's a bit odd. So now let's talk about that P value, which if you remember, Dr. Fishman quoted in his email, he quoted one of them. There are several in the study.
00:41:39
Speaker
What's important to keep in mind is that the P value by itself does not tell us the full picture. We need to consider the confidence interval and the effect size as well. So effect size can show how important a difference is between two groups or how strong a relationship is between different elements, different variables in a study.
00:42:01
Speaker
So confidence interval is used when there are a range of values and it tells us how sure we can be that the true answer falls within that range. Can you give us an example of what some of these values are that you're referring to? What are the values we're we're talking about here?
00:42:18
Speaker
So here we're talking about the values measured on the DEXA scans, either the pre-yoga DEXA scans or any of the follow-up DEXA scans that anyone provided.
00:42:30
Speaker
So that's your confidence interval. And then the effect size shows how meaningful a difference is between two groups in a study. Now, here's the thing with this study. We don't have two groups. It was only one group.
00:42:41
Speaker
There was no control group, right? So we don't know how meaningful the difference is because we only had one group. Yeah. And for more about the importance of a control group, listen to episode 51, where we do talk about this study in a lot of depth.
00:42:54
Speaker
And namely, we talk about the issue with not having a control group. Okay. So now, Laurel, can you please tell us and explain what is this P value? Okay. Before we do that, let's back up a little bit.
00:43:05
Speaker
So in research, when doing research, scientists are not trying to prove that an intervention caused an outcome. Instead, they are testing whether they have enough evidence to reject the null hypothesis, so that null hypothesis assumes the intervention had no effect.
00:43:29
Speaker
In biomechanics and kinesiology research, A p-value of less than 0.05 is commonly considered statistically significant, meaning there's less than a 5% probability that the observed results happen by chance if the null hypothesis were in fact true.
00:43:46
Speaker
A more clinically stringent threshold is 0.01, meaning that there's less than a 1% probability of the results occurring due to random chance if the null hypothesis were true.
00:43:58
Speaker
So again, a p-value does not prove causation. It simply tells us how likely it is that the study's findings could have happened due to chance. So in short, we don't want the study's results to be just due to chance or just a coincidence.
00:44:12
Speaker
A low p-value gives us more confidence that the observed effect is real, but it's only part of the bigger picture, which includes effect size, study design, replicability of the study, and also confidence intervals.
00:44:30
Speaker
Okay, so what were the p-values for the study by Dr. Fishman? For the people who were moderately or completely compliant with the yoga practice, these were the results, and we'll put the table in the show notes.
00:44:43
Speaker
At the spine, the p-value is 0.002, which is statistically significant, meaning it was not due to chance, right? At the hip, the p-value is not calculated.
00:44:55
Speaker
However, the small effect size and wide confidence interval suggests that it does not have significance. At the femur, the p-value is 0.05. This suggests that the effect is only barely significant.
00:45:08
Speaker
And then they looked at the p-value for those who fully documented their practice, which is a smaller group. So that's also linked in the show notes. Okay. At the spine, the p-value is less than 0.02.
00:45:20
Speaker
At the hip, the p-value is less than 0.01. At the femur, the p-value is less than 0.0002, which makes all the data statistically significant.
00:45:30
Speaker
Okay. However,
00:45:35
Speaker
because statistically significant is a very exciting phrase. But before you say, Sarah and Laurel, aren't you going to have to eat your words about this because the p-value says it's statistically significant? Statistically significant means it didn't occur by chance.
00:45:47
Speaker
But this study, and they say as much in the study, has many confounding factors, which are things that can distort or mask the relationship of the data and thus skew the results. I could spend a very long time on this, but we have done it in previous episodes. So here are just some of the most important confounders.
00:46:05
Speaker
And as we said earlier, the biggest one is that there's no control group. When there's no control group, we don't have a baseline for comparison. right? We can't say if people did not do yoga, this is what happened. And if people did yoga, this is what happened, right? So it's hard to say if the changes are due to the treatment or other external variables that we don't know about, right?
00:46:26
Speaker
It also means, believe it or not, that the placebo effect is an effect because participants might show improvements simply because they believe they could. And then other confounding variables like time, environment, personal characteristics can influence the results, but without a comparison group, we can't isolate out these variables.
00:46:45
Speaker
And so all of that to say that this gives us very limited generalizability, meaning we cannot necessarily apply the findings beyond the specific study conditions. So what you're saying, Sarah, is that the p-value given in isolation doesn't really mean a whole lot unless we look at some of the other aspects of the methodology of the study. Is that what you're saying?
00:47:07
Speaker
Yes. And that without considering the confidence interval and the effect size, we don't have any context for this statistical significance. Right. But Fishman in in his email gave us the p-value.
00:47:20
Speaker
Yes. Yeah. So here's another problem with the way this study was put together, which is selection bias, which is participants are not necessarily representative of the larger population that you're trying to generalize to, right? In this study, people signed up to do the yoga.
00:47:36
Speaker
And my understanding is that a lot of them were already doing yoga. And the other thing is if people who are already more health conscious are self-selecting, their bone density might naturally improve more than a broader population, right? And so then we can't generalize from that.
00:47:51
Speaker
We're also going to see issues here in this study with data collection. And one of the things, and and you know I can't speak to this very specifically, but DEXA machines are notoriously inconsistent.
00:48:03
Speaker
um Not that they themselves don't record what they're seeing, but there's a lot of variability between devices, right? In this study, scans are coming from like all different kinds of machines, right? Because my understanding, this is people worldwide. So they're not all coming in and getting a scan on the same machine is my understanding. If that's incorrect, I would love to be corrected, but that's my understanding. They didn't actually tell us otherwise though.
00:48:25
Speaker
So we can only assume. And the other issue with the data collection is that there's a lot of self-reporting, right? Everyone had to write down how much yoga they did and when. And it's not a very reliable way to collect data. People tend to have just very inaccurate recall or this thing called social desirability, right? They want to be the person who's doing this much yoga. So they're just going to say, I did it every day. And so we don't know if the participants really did the yoga routine exactly how and as much they documented. And so that might overestimate the true effect of the yoga itself. and Absolutely. They know they're supposed to be doing it.
00:48:58
Speaker
Like how many times have you known in your life for random things that you're supposed to be doing something? And when someone asks you if you're doing it, you bend the truth a little bit.

Comparing Yoga and Resistance Training for Bone Health

00:49:08
Speaker
Of course.
00:49:09
Speaker
I do it all the time, which means i do I do it once a month if I'm lucky. Sure. You go to the doctor, they say, do you drink? You're like no.
00:49:18
Speaker
but
00:49:21
Speaker
Anyway, the other thing we don't really know about because it wasn't clearly described in the study is if there were any competing interventions, right? If the participants were also engaging in other health interventions, like changing their diet or other forms of exercise alongside the yoga. So it's going to be difficult to attribute the observed changes in bone density to yoga.
00:49:39
Speaker
alone. We don't know this because there was that vague sentence about diet and medication and exercise, but we just don't, we have no information. And then improper analysis. So either incorrect handling of the outliers or missing data can affect the results. And I talked about the the unusual analysis choices.
00:49:56
Speaker
you know Dr. Fishman, in his email, pointing to the p-value, but without the effect size and the confidence interval also considered, p-value alone is not enough. The lack of control group alone makes this study less reliable for establishing cause and effect relationships. I would go ahead and say much, much less.
00:50:15
Speaker
The bottom line is this. We mean this with no disrespect to the researchers, but the quality of this study is extremely low. And because of that, we cannot accept the results as proving what the title states.
00:50:28
Speaker
Okay. Thank you for sticking with me through all of that statistics. so Hopefully it wasn't too brutal. Let's get back to the email. Laurel, what else does he have to say? Sarah, statistics never sounded so good. Thank you.
00:50:40
Speaker
Back to the email. Dr. Lauren Fishman writes, quote, the magnitude of force brought to bear on the bones is significantly greater than you estimate it for several reasons, unquote.
00:50:54
Speaker
Okay, so here's the thing about that. We actually aren't estimating. the amount of force applied to bones. We are actually going on the available quality research around what the mechanical loading requirements are for bone building and what quality randomized controlled trials have found when pitting high intensity resistance impact training against low intensity formats in controlled trials. We are not estimating the forces brought to bear on bones.
00:51:25
Speaker
We are looking at the evidence. So here are a couple of studies that we'll link in the show notes that are randomized control trials and or do provide evidence as to the mechanical loading requirements for bone, which are high.
00:51:42
Speaker
Liftmore trial, this was a landmark study. We've talked about extensively on this podcast. We had insights from Dr. Belinda Beck in a previous podcast episode. Definitely listen to that. We've got Liftmore M, which was a similar study done on men, whereas Liftmore was done on women.
00:51:58
Speaker
Then we have MedXOP. This trial compared Pilates, buff bones, to high-intensity resistance and impact training, showing that Pilates had no effect, while HI-RIT, high-intensity resistance and impact training, increased bone density.
00:52:13
Speaker
There was ah meta-analysis on high load resistance training. I'll link that in the show notes. This study found that high load resistance training, HLRT, significantly increased bone mineral density in the lumbar spine, femoral neck, and total hip with the strongest effects in the lumbar spine.
00:52:28
Speaker
We also have a systematic review on Pilates and yoga. A 2020 study found no significant improvement in BMD with Pilates or yoga for adult women based on randomized controlled trials comparing these exercises to control groups.
00:52:42
Speaker
So the main topic here, as it pertains to our conversations around Dr. Fishman and his claims that yoga builds bone is, does yoga build bone? Yoga is not high intensity strength or impact training, nor does practicing yoga involve high forces like the type we experience with high risk.
00:52:58
Speaker
So it is actually implausible that yoga builds bone. A key point in this discussion is that bone adaptation requires high impact or high load stimuli as explained by the well-established mechanostat model.
00:53:16
Speaker
In his 1987 paper, Bone, Mass, and the Mechanostat, a Proposal, Dr. Harold Frost introduced the idea of the, quote, mechanostat to explain how our bones change and adapt based on the stress they experience.
00:53:32
Speaker
The word mechanostat is like the word thermostat, only for bone. Just like a thermostat controls the temperature in a room by responding to changes in temperature and adjusting the heating and cooling system, accordingly, a mechanostat is a theoretical system that regulates bone density by responding to mechanical loading or strain on the bone.
00:53:53
Speaker
When the mechanical load on bones decreases, like it does in disuse, the mechanostat senses it and triggers bone resorption. Resorption means breakdown.
00:54:05
Speaker
And when the load increases, such as through osteogenic exercise, it stimulates bone formation to maintain bone density. Osteogenic means bone building exercise, so not all exercise is bone building, which is the crux of what we're talking about here.
00:54:18
Speaker
The mechanostat model shows that bone adapts to mechanical strain and it takes high magnitude or high rate loading. So high magnitude would be heavy strength training, high rate loading would be impact training to trigger bone growth.
00:54:32
Speaker
Activities that apply high magnitude of load, heavy weightlifting, high rate of loading, plyometrics, and other impact activities create levels of strain that exceed the bone's adaption threshold.
00:54:44
Speaker
Sorry, you mean adaptation? Well, adaption is another way to pronounce it. I thought you would know that as a Brit. I did a whole mentorship with Chris Beardsley, who is British, and he kept saying adaption, adaption, adaption. I was like, um, we say adaptation. Is it the same thing? as Yes.
00:55:00
Speaker
Oh, okay. That's a new one to me. I don't know that one. The Bones Adaptation Threshold. Activities that apply high magnitude of load, heavy weightlifting, high rate of loading, plyometrics, and other impact activities create levels of strain that exceed the bone's adaption threshold.
00:55:18
Speaker
Yoga, on the other hand, is generally a low-impact activity with slow movements and prolonged static holds. If you think about it, yoga exhibits the exact opposite qualities you'd want in an osteogenic exercise, according to the mechanostat theory.
00:55:36
Speaker
And so therefore we can presume and we have evidence to suggest as well, quality evidence in fact, that yoga produces minimal strain rates. Yet Fishman claims that yoga poses apply more forces to bones than we've estimated.
00:55:52
Speaker
What is he basing this claim on? What instruments does he use to measure if this is true? We aren't aware of instruments that would be able to measure this currently. Also, what research has looked specifically at the magnitude and rate of loading bones experience in yoga?
00:56:09
Speaker
Exactly none to our knowledge. Dr. Fishman's claims are largely based on conjecture and speculation. He believes that muscle engagement in yoga is high enough to strengthen bones, and he believes that certain poses involve loading forces high enough to strengthen bones.
00:56:29
Speaker
However, these beliefs haven't been quantitatively measured, tested, or proven. And as we know from the mechanostat theory, it's not just any old amount of muscle engagement that builds bones.
00:56:45
Speaker
It's more specific than that. It's the high magnitude and high rate of loading from high intensity resistance and impact training.
00:56:58
Speaker
Our bone density course, Lift for Longevity, is your step-by-step guide to building strength and protecting your bones with heavy lifting. And if you join the waitlist now, you'll get exclusive monthly free content, plus the biggest and only discount we offer when enrollment opens.
00:57:14
Speaker
You might be wondering, how do I know if I'm lifting heavy enough to actually improve my bone density? How can I keep getting stronger without getting injured? What's the best way to modify lifts if I have joint pain or past injuries?
00:57:27
Speaker
How do I fit strength training into my busy life and make it a habit that sticks? If you've ever had questions like these, Bone density course lift for longevity will give you the clear science back answers you need.
00:57:39
Speaker
But here's the thing. We only open enrollment twice a year. That's why the wait list is the best way to stay in the loop. Sign up now to get expert insights, strength training tips, and first dibs on the best deal we offer. Your bones will thank you. Join the wait list now via the link in the show notes.
00:58:03
Speaker
He goes on to say that, and this is a quote, many yoga poses pit agonist versus antagonist doubling the forces on the bones, end quote. He makes this claim all over yoga for osteoporosis as well.
00:58:16
Speaker
Yeah. So this claim that many yoga poses pit agonist versus antagonist doubling the forces on bones doesn't really hold up under scrutiny. The idea that simply engaging opposing muscles in yoga will somehow double the forces on your bones is frankly misleading. Let's break it down. So first we need to understand what agonist and antagonist muscles actually are. You listeners may have a good idea, but let's just make sure we're all working with the same information.
00:58:41
Speaker
So the agonist is the muscle or group of muscles that are contracting in order to move a joint or to hold it in place. And the antagonist is the muscle that is resisting that movement. Generally speaking, when you are using your agonist muscles to create movement,
00:58:55
Speaker
the antagonist muscles are relaxed or they're being stretched so as not to obstruct the movement that you are doing. So for example, if you are picking a brick up and smashing it against your head in frustration, one of the muscles that has to work is your biceps and your triceps have to be relaxed. Otherwise you will never get the brick to smash against your face.
00:59:16
Speaker
So, okay. So in order for me to both contract the agonist and the antagonist muscles at the same time, the For some yoga poses requires consciously adding an isometric contraction of the antagonist muscles because presumably it has to be isometric because I'm not trying to leave the pose.
00:59:32
Speaker
So for example, imagine yourself in a bridge pose and you are wanting to counter the agonist hip extension created by your glutes and hamstrings. You then also have to isometrically contract your antagonist hip flexors.
00:59:48
Speaker
Or if you consider the front leg in warrior two, which is one of the poses in the study, as you're coming into the pose, your quads are eccentrically contracting to resist knee flexion and your glutes and hamstrings are also eccentrically contracting to resist hip flexion. Once you're in the pose, both groups are contracting isometrically. So yes, it is possible in some yoga poses that both groups will naturally be engaged at the same time, right? But not all yoga poses. Some poses would require a conscious instruction to contract.
01:00:16
Speaker
But regardless, just because both muscle groups are active does not mean we're suddenly doubling the forces on our bones. It's actually a really inefficient way to hold a lot of poses. it It's not required. And therefore, your nervous system is not going to select that coordination of engagement. You would have to override centuries millenniums of of evolution, really, because we're energy conserving.
01:00:44
Speaker
At baseline. And that is a very inefficient way to exercise. And here's the thing as well. The forces on your bones depend on the total magnitude of load you're putting on them or the rate of load, not just how many muscles you're engaging, right? While activating opposing muscles may create some tension in the muscle,
01:01:05
Speaker
It is not the same as adding substantial force or speed to your bones in a way that would stimulate bone remodeling. Yoga just doesn't provide this kind of high resistance or impact needed for bone building in the same way that weightlifting or high impact activities do.
01:01:21
Speaker
So while it's true that yoga can engage muscles and apply some force to the bone, the claim that it's doubling that force just does not stand up to the science of bone adaptation. Also, that's a quantitative claim.
01:01:32
Speaker
Yes. F times two. Yes. When I hear something that is so specific and quantitative, I definitely want to know where that number came from. Not only is it implausible that co-contraction of agonists and antagonists muscle groups in a yoga pose doubles forces on bones, as I said, it's inefficient. It's an incredibly inefficient way to hold a yoga pose, and there's no evidence that opposing muscle groups...
01:01:57
Speaker
Contracting simultaneously, as Sarah said, doubles the mechanical load on bones in research, so it lacks plausibility and evidence. Muscle contractions do contribute to bone loading, but peak forces exerted during yoga are far lower than those from activities like jumping, sprinting.
01:02:14
Speaker
heavy resistance training, which are known to stimulate osteogenesis. I don't care how hard you squeeze your quads or firm your buttocks in a standing pose. Those are cues I used to give all the time as a newer yoga teacher. Firm your quads, squeeze your quads, firm your buttocks.
01:02:30
Speaker
Lift your kneecaps. Yeah, lift your kneecaps. You're really only ever dealing with body weight at the end of the day. So you can go ahead and superimpose a lot of unnecessary effort on top of the resistance you're undergoing, but the resistance at the end of the day is low.
01:02:49
Speaker
In certain poses, body weight does constitute a significant resistance, but not in the poses that are looked at in Fishman's study, actually. We're not looking at crow pose in that study. We're not looking at handstand in that study.
01:02:59
Speaker
lot of... ah poses we're looking at involve lying on the ground and sitting down yeah additionally bone cells specifically osteocytes right those are bone cells respond to dynamic loading rapid strain changes right not static holes yoga's slow and sustained poses fail to generate what's called the fluid shear stress fluid shear stress necessary for osteocyte activation and subsequent bone remodeling. So osteocytes are the builder cells of bones.
01:03:34
Speaker
This is something that Rubin et al. discusses in their research. That study is linked in the show notes. They found that osteocytes primarily respond to dynamic loading or quick strain changes rather than to static holds like those found in yoga poses.
01:03:49
Speaker
While the Rubin study doesn't directly look at yoga, it does highlight the kind of strain necessary for osteogenesis. something yoga fails to provide. So while yoga certainly has many health benefits, it's wonderful for improving your flexibility.
01:04:06
Speaker
It is a very effective relaxation type practice that you can engage in and mindfulness practice. It's also low impact and low resistance in nature, which makes it not a very good bone building exercise. It doesn't generate the level of strain required for meaningful bone building. If you're hearing this word strain a lot and you you're curious as to what exactly we're talking about, listen to the episode with Professor Belinda Beck where she talks about strain and why bones need a strain to make themselves stronger.
01:04:41
Speaker
Okay, also when Dr. Fishman suggests that we would co-contract agonist and antagonist muscles to, quote, double forces on bones, he's describing voluntary isometric muscle contraction.
01:04:52
Speaker
So voluntary means we decide, I'm going to squirt. squeeze all the muscles around my hip or shoulder or trunk as hard as possible while I hold this pose. In other words, it's not involuntary. It's not a reflex. We override probably and in a lot of poses what would be the way our nervous system would self-select muscle engagement patterns to impose ah additional muscle engagement on top of that.
01:05:15
Speaker
Okay. So let's let's do a little experiment. Okay, listeners. ah Pick a part of your body that you want to try to practice this voluntary isometric muscle contraction for, right? Maybe it's your hips, your shoulders, your core.
01:05:31
Speaker
And I want you for the next couple seconds to try to engage all the muscles of that area all at once as hard as possible, right? Go.
01:05:47
Speaker
You should see Sarah's face. She looks like she's... I won't say it. So, so, okay, hopefully you ran that little experiment. Now imagine doing that in your yoga practice.
01:05:59
Speaker
In some, we're all aspects of your body during a pose. And also were participants instructed to do this? Yeah. yeah well He does mention his teacher and the way his teacher teaches later in the email. We'll get to that.
01:06:11
Speaker
In part one of our longevity series of this season about strength, episode 90, we discussed two different types of strength, isometric versus dynamic. yeah These are different ways to exert force.
01:06:24
Speaker
Isometric contraction is tested against an immovable object, typically. So right there, that eliminates our ability to test this in yoga.
01:06:35
Speaker
Well, it might explain why it hasn't been tested yet. I won't say that it completely eliminates our ability because who knows? Science is amazing and ever-evolving. But we're not able to test this in yoga given the tools that we currently have because we are not exerting isometric force against an immovable object in yoga.
01:06:52
Speaker
Our body is the source of resistance and it is a movable object. So if we exert enough force in, say, our quads in Warrior two our knee will simply straighten.
01:07:04
Speaker
Now, if we're simultaneously exerting as much force as possible with our hamstrings so that our quads and hamstrings both get to contract isometrically, that is, yes, isometric contraction.
01:07:15
Speaker
It's also incredibly inefficient, but it's not maximum voluntary isometric contraction because ultimately the body in this scenario is not like a wall or not like a bar strapped to a cage.
01:07:27
Speaker
It is movable, not immovable. According to research, maximum dynamic muscle force production is moving resistance through ah particular range of motion.
01:07:40
Speaker
Okay, so that to say that when bone building is tested using exercise intervention, the type of muscle contraction being studied is actually dynamic maximum force production and not maximum isometric muscle force production.
01:07:54
Speaker
But that aside, here's the thing I want you to also know. In addition to taking on the fact, okay, that we don't co-contract muscles to maximum in yoga poses. We don't exert maximum isometric contraction against immovable objects in a yoga pose.
01:08:09
Speaker
Also, isometric muscle contraction, the type we'd be aiming for, presumably for bone building in yoga, maximum to increase our bone mineral density. This type of muscle engagement, isometric contraction, is typically performed at a lower level of force than it is when someone engages in dynamic muscle force production. In other words, when we ask someone to engage in dynamic muscle force production, we typically get higher forces than when we're engaging in isometric force production, okay? While isometric contraction can generate high muscle tension, all right, dynamic contractions typically produce greater total force without getting too much into the weeds, all right?
01:08:51
Speaker
Peak muscle tension and total muscle force are different things, okay? Basically, dynamic movements like the squat, deadlift, and strict press recruit more total muscle fibers and activate both eccentric and concentric contractions.
01:09:07
Speaker
Additionally, dynamic exercises take advantage of the stretch shortening cycle where muscles and tendons stretch and then rapidly contract, increasing force production. In contrast, isometric contractions involve the muscle remaining in a fixed position, producing high tension at that moment, but they don't engage the muscle through a full range of motion.
01:09:28
Speaker
So while both types of contractions have their place, dynamic movements generally produce higher overall force due to higher muscle fiber recruitment and the involvement of more muscle groups.
01:09:38
Speaker
That right there is another reason why yoga is probably not going to be great for osteogenesis because it's isometric in nature. It's also not probably maximal isometric force production.
01:09:51
Speaker
But if we remove that and we just look at the fact that it's isometric, that's also an issue here. Here's another quote about being able to muster up adequate load for yoga to be bone building. This is a direct quote from the email.
01:10:08
Speaker
Iyengar yoga, and then in parentheses, my teacher, end parentheses, insists you try quite hard. So trying quite hard is what's called an unfalsifiable claim.
01:10:22
Speaker
And we talked a lot about this in episode 82 called Weird Science, when it doesn't all add up. There will be a link in show notes. An unfalsifiable claim is a statement or hypothesis that cannot be proven false no matter what evidence is presented.
01:10:35
Speaker
This means that there's no possible test, observation, or experiment that could disprove it, right? How do we test trying quite hard versus not trying quite hard? What is a measurable unit of trying?
01:10:45
Speaker
And it's usually vague or broad, right? We can't pin it down to something testable. All of this puts the statement outside the realm of the so scientific inquiry. Unfalsifiable claims are really common in pseudoscience where ideas are presented as fact but cannot be tested or disproven.
01:11:02
Speaker
In science, testability matters. Health recommendations should be based on measurable, replicable interventions, not personal anecdotes. This is also This is kind of an irrelevant point to the conversation, right? one Which is one of the many distractions in his email.
01:11:18
Speaker
The question is whether yoga itself is impactful enough to stimulate bone remodeling, not how hard someone is trying or which teacher they're learning from. Quite hard is not a measure of load.
01:11:32
Speaker
It's just not. Yeah. All right. So back to the email, Dr. Fishman writes, quote, the force acceleration in yoga is not real slow. but you're right.
01:11:44
Speaker
It's not as rapid as weightlifting. Okay. So this, I believe, and I'm just guessing here, is in response to him assuming that we're critiquing yoga as not an osteogenic format of exercise because the rate of loading isn't high enough.
01:12:03
Speaker
All right. But that's not actually our critique on yoga. Our critique is that the magnitude of load is not high enough. So he's bringing up rate of loading, He's acknowledging that yoga's force acceleration is, quote, not real slow, but, quote, not as rapid as weightlifting.
01:12:23
Speaker
But here's the thing. We actually, like i said, never said weightlifting builds bone because of rate of loading, nor are we saying that yoga doesn't build bone because of rate of loading. Rate of loading is actually not a force characteristic that we're really that interested in with weightlifting.
01:12:40
Speaker
It's not the primary force characteristic in question when we're looking at why weightlifting is osteogenic. The real reason weightlifting is osteogenic is because of the magnitude of force, which is a separate force characteristic.
01:12:53
Speaker
It's because weightlifting, if you're using heavy loads, places high resistance against the body, which the muscles then must overcome and the muscles then create internal load on the bones.
01:13:06
Speaker
This is a different force characteristic and it seems like they're being conflated.
01:13:15
Speaker
Okay, so rate of loading, on the other hand, um that's more relevant for activities like impact training, for understanding why impact training would be osteogenic. So think about jumping, hopping. This is where rapid, high-impact forces are applied to the bones when you land.
01:13:33
Speaker
So Fishman's response seems to miss the point. It seems almost to misrepresent the mechanism of bone adaptation that we'd be looking at when comparing different exercise formats. It seems to be sidestepping the real issue, which is still that yoga doesn't generate enough force to trigger meaningful bone growth.
01:13:53
Speaker
So if we continue with the email, he goes on to write, quote, as for the cellular accommodation, we now have people in our studies for many years who are still going up in their BMD in a pretty linear fashion, unquote.
01:14:07
Speaker
So then I asked a follow-up question about this because I was confused what he was talking about. I said, you referenced 12 people that you have been following for six to eight years. Is this in any published research that we can access? Or is this new as yet unpublished study that you're currently working on?
01:14:21
Speaker
And he responded, quote, this is not a study. These are just people that are still my patients and have continued doing the yoga we gave them that long ago and get DEXAs every two years. This is in contradistinction to the medicines, meaning medication for osteoporosis." end quote Okay, well, we also know nothing about any other activities these people may be doing now.
01:14:43
Speaker
We don't know the speed with which their bone mineral density is improving. We don't know any other details that might give context to the relative value of what he is saying about these 12 people. people And, you know, it's this is casual conversation in an email. It's very anecdotal.
01:14:59
Speaker
There's a lot of other things I could pick apart about it, but let's just move on. So then he writes, quote, a study by Rubin at Sheffield in England with turkey wings does show, and then he put quotes marks around this word, unusual pulls on bones do more for building them, unquote.
01:15:15
Speaker
Okay, so let's specifically talk about why yoga building bone is scientifically implausible. And to do this, we're going to talk turkey. I was very proud of myself for that. Yeah, very good. Turkey studies, that is. So there are two studies done on turkeys by Ruben et al. that look at mechanical strain, which is the scientific term for what happens to tissue when we load it.
01:15:39
Speaker
So in this Turkey study, they compared total disuse, so not using the bone at all, continuous compressive load, which is a static load, and intermittent loading.
01:15:50
Speaker
So they had three different groups and the effect of each of those types of strain or force on bone mineral density. And what they found was that for the disuse group, there was a decrease in bone mineral density, which is what we would expect, right? They weren't using it's use it or lose The static compressive load group did not see enough strain on the bone to prevent the same decrease in bone mineral density as the disuse group.
01:16:15
Speaker
It was only the intermittent loading group that not only prevented bone loss, but saw a cross-sectional area increase, meaning the bone got bigger. I just am clarifying. There were three groups, the disuse group, the group that got nothing, the group that got sustained loading that was never removed from the beginning to the end of when it was applied, right?
01:16:38
Speaker
100 seconds. That's the sustained group? Yep. And then what's the third group? The third group is dynamic intermittent loading. The intermittent loading group, which is the third one, the dynamic intermittent loading group not only prevented bone loss, but saw a physical cross-sectional area increase. The bone got bigger. And isn't that actually disproving what Fishman is saying?
01:16:56
Speaker
It's all disproving it. Okay. I would say that this study actually, if anything, throws doubt on his claims. Yes, I agree. Because the intermittent loading group saw the improvements.
01:17:07
Speaker
If we're going to leave aside all of the other differences that we would have to leave aside to be able to make this comparison, these are turkeys that there are pins in these turkeys' bones and are load that are loading the turkeys' bones with pins, not muscle engagements.
01:17:20
Speaker
Yoga doesn't involve intermittent loading, at least according to how his study conducted the the exercise intervention, right? They were holding the poses for 30 seconds, you said? Yes, it was and it was Iyengar yoga, which is a type of yoga that is known for holding poses. It's not a vinyasa yoga. Exactly, because a point that Dr. Fishman has tried to make on blog posts on the Yoga You site is that because yoga is not a cyclical exercise like running, it's not, yes, okay, poses are held for however long you decide to hold them, right? It's completely variable. The poses continuously change. He's used the phrase, the muscles exert tension via the tendons on the bones from every conceivable angle, right? Okay, so maybe that's why he's referencing this turkey study. We don't actually know. i would say that this turkey study suggests that prolonged force is probably going to eliminate it as osteogenic because the bone in these turkeys was responding rather to the intermittent loading. We know that dynamic heavy strength training is dynamic, right? It's not sustained.
01:18:19
Speaker
We also know that impact training is osteogenic, right? loads are experienced rapidly. So I'm not sure why he's pointing to the study. We don't know. But yes, so cellular accommodation is definitely something you want to consider. And why, for example, we talked with Dr. Beck about this, why running, especially at longer distance running, which is going to happen at lower speeds, is not osteogenic. You would think it would be. It's an impact sport.
01:18:42
Speaker
It's not. It's too repetitive. And I think this would also be a good place to put in ah quote from our conversation with Dr.

Discussion on Effective Osteogenic Exercises

01:18:50
Speaker
Beck, because she also refers to this specific study.
01:18:59
Speaker
Probably the the thing that distinguishes heavy lifting or any kind of lifting and impact is the speed of loading. And I think that's what's key because If you look at the animal research, we know that high strain loads from Reuben and Lanyon's turkey work back in 1985, 1984, they showed really clearly there's a dose response. The heavier the load, the more the bone responds.
01:19:24
Speaker
But then later it became evident that you could actually apply lower loads if you applied them fast. So the rate of loading is important too. So I think if I, in my head, I'm thinking about that osteocyte syncytium, that's the network of bone cells bathed in fluid, and I'm thinking high strain means bending the bone quite a lot, so it's really squeezing the fluid quite a lot.
01:19:51
Speaker
Low strain quickly is more bending it fast and shaking it up. So both ways, are stimulating the cells to adapt, but it's in a different way.
01:20:04
Speaker
Very cool. That brings us nicely to our next question here. Can you tell us a little bit about cellular accommodation? This idea that bones get bored, so to speak, when the stimulus they're experiencing is too repetitive or goes on for too long of a duration?
01:20:22
Speaker
Yeah, so I can't tell you why that happens. I'm not a molecular biologist and I've never gone down that rabbit hole. But certainly we know that there is no point giving the same stimulus over and over to a bone cell because, again, Ruben and Lanyon showed that 36 cycles of a single mechanical load was exactly almost exactly the same 360 or the same stimulus. It just stops reacting because it goes, okay, enough, I've heard you.
01:20:54
Speaker
So translating that to the human condition, and I just told this to my students in class yesterday, you would get more response out of bone from sprint training than marathon training.
01:21:11
Speaker
Remember that you're gonna get higher muscle forces from people if you have them move a heavy weight, not if you ask them to squeeze their muscles really hard because their teacher teaches them a certain way. Moving on. He then says, quote, I noticed the gulf between people doing research and those using research in their daily lives or businesses.
01:21:30
Speaker
You come down rather hard on my, quote, blinders and, quote, only doing yoga. But of course, this was a study. You can't study everything at once. Okay, so he says there's a difference between people out in the field doing research and people who look at research for their business.
01:21:46
Speaker
And I agree. We agree. That's absolutely true. Creating solid research that is high quality is a very difficult, pretty thankless activity. And it's even worse when your research doesn't actually prove what you want it to.
01:21:59
Speaker
you're You're supposed to not want it to prove anything, though. you're supposed to be unbiased.

Criticism of Yoga's Efficacy in Osteoporosis Treatment

01:22:03
Speaker
Okay, but I would argue that this gulf also applies to companies like Yoga U or the many other yoga teachers or brands that are teaching yoga for osteoporosis or posting on social media about how yoga builds bone. Or AARP.
01:22:17
Speaker
Yes. Or Harvard Health. right? Should know better. In this case, these are people who are choosing to not be as rigorous as we believe they should be in their assessment of what Fishman's paper actually shows. There's no mention from him of their wholesale adoption of his claims without deeper analysis in order to sell classes. If you're going to use research to back up what you're selling, it better be fucking good research. Amen.
01:22:44
Speaker
And this is another appeal to a emotion here in this instance that we are, you know, coming down rather hard on his blinders and only doing yoga. ah We agree. You can't study everything at once, but that's not what we're talking about here. We're coming down rather hard on the fact that his study is not sufficient proof to go around letting other non-researchers make money. Yeah. And to sell an exercise and intervention to people that will have real life health consequences, like real life ones that we hear about in emails all the time.
01:23:12
Speaker
I thought the yoga was enough and I just got a diagnosis of osteopenia or osteoporosis. I guess the yoga wasn't enough. Right. All right. So back to the email, he writes, quote, in my working with people not in the studies, I frequently recommend weightlifting. I have not seen this recommendation made by Dr. Fishman anywhere in any of the published work, blogs and whatnot. So perhaps he should be more publicly vocal about it.
01:23:42
Speaker
um He is very publicly vocal about the benefits of yoga for bone building. He's written an entire book about it that leads with a very high level of confidence extolling the benefits of yoga for bone building, not the benefits of lifting heavy weights. Remember at the beginning of the episode where he actually cast a lot of doubt on the safety of weightlifting as well as the benefits of weightlifting in order to pit it against yoga and show that yoga was in fact superior to weightlifting?
01:24:08
Speaker
We'd love for Dr. Fishman to be more publicly vocal about the benefits of lifting heavy weights and engaging in impact training for bone building, especially in the work that he does with yoga people who tend to be perimenopausal and postmenopausal women who are or will experience a speeding up of bone loss associated with decreasing estrogen levels.
01:24:27
Speaker
We'd love for Dr. Fishman to stop spreading health misinformation about yoga as osteogenic. This misinformation has real-life health consequences for real people.
01:24:40
Speaker
Yet we are not aware that he makes any recommendations for weightlifting publicly. We are not aware that he has made any effort to correct the misinformation he has spread.
01:24:50
Speaker
Back to the email. He writes, quote, There are articles, plural, showing that yoga builds dynamic balance, improves posture, increases muscular strength, range of motion, coordination, parentheses, C surely tells for thickening of the third layer in the cortex too, and lowering anxiety.
01:25:11
Speaker
So this is back to yoga's benefits. And lowering anxiety, all of which mitigate the risk of fall and fracture. I'm talking about multiple articles on each of these virtues of yoga. Okay.
01:25:24
Speaker
So we looked through 263 publications authored by Shirley Tells and were unable to find any on the topic of yoga and bone health, let alone any that showed thickening of the third layer of bone cortex as a result of yoga.
01:25:39
Speaker
And in fact, only two of her papers were even remotely relevant to the subject of bone building. One was a randomized controlled trial to assess pain and magnetic resonance imaging, which Based on and MRI-based structural spine changes in low back pain patients after yoga practice, the structural changes made in 12 weeks yoga intervention were not deemed statistically significant. In this case, structural changes would be bone remodeling type changes.
01:26:05
Speaker
Not statistically significant. I also looked for citations in Yoga for Osteoporosis, the book that Fishman and Saltonstall have authored together. I looked for citations in that book authored by Tells and didn't find any.
01:26:20
Speaker
So that turned out to be a dead end. And then and the rest of what he says here amounts to ah rhetorical device known as the red herring. So when he mentions that yoga builds dynamic balance, improves posture, increases muscular strength, range of motion, and coordination, these are red herrings.
01:26:38
Speaker
So a red herring is a rhetorical device that serves as a misleading distraction. It shifts the focus away from the actual topic, yoga as an osteogenic exercise intervention, and instead leads the conversation down an unrelated path.
01:26:51
Speaker
Red herrings are frequently used to evade scrutiny or avoid directly responding to criticism or counter arguments by diverting attention to something that feels like it's part of the discussion, but ultimately is not.
01:27:06
Speaker
So when Fishman brings up things like dynamic balance or reducing the risk of falls with yoga, he's using a red herring to sidestep the real issue, which is whether or not yoga can actually build bone in a meaningful way.
01:27:24
Speaker
Fishman mentions that there are several studies showing that yoga improves balance, posture, strength, coordination, and even reduces anxiety. While these are important benefits, they're a red herring in this context.
01:27:38
Speaker
They don't address the core question of whether yoga actually builds bone. Fall prevention is obviously important, but it's not a substitute for increasing bone mineral density through osteogenic loading, the kind of high resistance or impact exercise that triggers real bone growth.
01:27:57
Speaker
By shifting the conversation to these other health benefits, shifting the goalposts, right, which is a tactic we discuss in episode 84, six ways to spot exercise for osteoporosis misinformation, Fishman is avoiding the central issue.
01:28:13
Speaker
Yoga doesn't meet the mechanical requirements for bone adaptation. Instead of proving that yoga can meet the mechanical requirements for bone adaptation or providing some evidence, quality evidence to suggest that it can, he instead introduces a separate health benefit, several, to make yoga seem more effective,
01:28:34
Speaker
than it really is when it comes to bone density. Yeah. and there are some more red herrings. Here's another quote from the email. He says, I don't know what that video says, but we now have over 250,000 hours of people doing the yoga we recommend without a single fracture, herniated disc, meniscal tear, nothing serious, end quote.
01:28:54
Speaker
I don't know what video he is referring to, but... 250,000 hours. I first read it as 250,000 people. And I was like, wow, that's a really impressive number of people. But then I realized it's hours. So then how many people?
01:29:07
Speaker
And so I asked him how many people the 250,000 hours was referring to. And this is what he said, quote, over 108,000 hours. And then in parentheses, he does the math, which is 741, which is the total people doing the study times 365 days a year.
01:29:24
Speaker
times two, two years, divided by five, which is the 12 minutes a day, assuming they all did the yoga daily for 12 minutes for two years. Why is it divided by five again? ah Because that's the 12 minutes. Okay.
01:29:35
Speaker
Because five as a 12 times five is 60. Okay. you but It took me a while to figure that out. The five was confusing me for a bit. But here's the thing. We know that this is not an important detail, but we know that this is not correct already because you already told us in the study that of the 741 people, they didn't do it.
01:29:50
Speaker
people they didn't do it All of them did not do it days a year for two So anyway, and then he goes on to say, quote, well, that was 10 years ago, and now we have over 400 teachers teaching it.
01:30:02
Speaker
So 250,000 hours is quite ah conservative estimate. Judging from my email, there are many people doing the yoga we recommend without a teacher, too. We have given out thousands of discs, end quote.
01:30:14
Speaker
Okay, so more important than how accurate the 250,000 hour claim is, this is another red herring topic shift away from does yoga build bone? He's talking about how yoga is safe.
01:30:25
Speaker
Yoga's safety does not prove that it meets the mechanical requirements for bone adaptation. We already have said this and we know we need high enough resistance or impact to trigger bone remodeling and safety alone does not speak to whether yoga can do that. So it's great that yoga is safe, but it's not a substitute for the kind of intensity needed for real real bone building.
01:30:45
Speaker
And, you know, not only have we never claimed that yoga is dangerous, because it's consistently shown in research that it's not dangerous, we in fact, highlight yoga safety in many episodes, including the one he listened to, right? There's lots of activities that are both safe and not meaningfully osteogenic.
01:31:03
Speaker
Yeah. All right, yeah back to the email, he writes, quote, there are three twists in the series we're talking about, So we are definitely pro twists and have been for a long time.
01:31:16
Speaker
Twisting is usually painless to the side opposite a herniated disc, but painful to that side. So yeah we're not skipping sentences in this email.
01:31:30
Speaker
Also, I, we're not, this is not, it seems non sequitur. Yeah. Right. But anyway, he writes, this is what he writes again. Um,
01:31:40
Speaker
The main topic here, I'm just going to keep coming back to it again and again and again. This is the claim we're contesting, that yoga builds bone. um Okay? not that Not that it's safe or unsafe.
01:31:52
Speaker
Not that it helps with balance. Not that it reduces anxiety. We're actually contesting one single claim, which is does yoga build bone? Because that is the crux.
01:32:04
Speaker
That is the thing we need to know, actually, if we do in fact want to say that yoga builds bones. We have to first know, does it meet the biomechanical requirements for bone building?
01:32:15
Speaker
And then it does, right, we can say, and it's also great for all these other reasons. But we can't start with it's great for all these other reasons and say that it builds bone. We have to first start with whether or not it meets the biomechanical requirements for bone building.
01:32:29
Speaker
And so this is another red herring because now he's talking about twists and whether twists are safe. and how they are purportedly painless to the side opposite a herniated disc, but painful to that side.
01:32:42
Speaker
He wants to talk about this, and i don't know whether or not those claims are true. I'm going to, again, remain at a healthy level of skepticism toward everything that he's just written there about twists, but...
01:32:55
Speaker
The safety of twists or pain experienced during twists for disc herniations doesn't prove that yoga meets the biomechanical requirements for bone adaptation. Right? We need exercises that apply on enough force or impact to stimulate bone remodeling.
01:33:10
Speaker
And the safety of twists in yoga doesn't speak to that at all. Yeah. So then he goes on to say, quote, work by Murshid Sanaki at the Mayo Clinic shows that forward bending causes the wedge fractures so common in osteoporosis, end quote.
01:33:27
Speaker
So yes, wedge fractures, yes, they are common in osteoporosis and they can happen with forward bending. But this study that he's referring to is not as ironclad, I would say, as it seems. And we have an entire episode coming out soon about this study and how it has informed a lot of yoga for osteoporosis or Pilates for osteoporosis classes. So we're not going to get too much into this study right here because we're talking a lot about it pretty soon. All right, and back to the email. Fishman writes, quote, all we've seen is some stiff muscles in beginners, something you might encounter too, unquote.
01:33:59
Speaker
ah So again, he's he's speaking around the topic of safety, and he's saying, you know, people just are a little stiff if they're beginners, and maybe you've seen that too, and I'm like, well, I don't... yeah, muscle soreness is a thing. I'm not sure how this has anything to do with yoga for bone building.
01:34:15
Speaker
He then goes on to write, quote, concerning variety, we have three series of 12 poses each and three versions of each pose with adaptations by certified teachers, unquote.
01:34:28
Speaker
Okay.

Yoga vs Weightlifting: Effectiveness for Bone Density

01:34:29
Speaker
Again, the main topic here is does yoga build bone? But Fishman is now introducing another red herring when he points to his pose adaptations and the certification of his teachers.
01:34:42
Speaker
Details that don't address the central question. The details of his yoga program, ah even with the adaptations and the certified teachers, still don't prove that yoga is osteogenic.
01:34:53
Speaker
They don't show that yoga asana meets the biomechanical requirements needed to stimulate bone remodeling. While a well-structured program is certainly important, If the exercise you are structuring well is the wrong type of exercise for your intended goals, it doesn't actually matter how well it's structured.
01:35:12
Speaker
I could give a marathoner a very well-structured strength program, and they could just engage with that well-structured strength program thinking they were preparing for their next marathon, and they would be very sad.
01:35:27
Speaker
to find out that that very well-structured strength program did almost nothing for their performance as a long distance runner, okay? So it doesn't matter, right? It doesn't matter if your intention is to build bone, you first have to choose the right tool for the job.
01:35:45
Speaker
And the email goes on to say, by the way, a friend was offended by another writer's criticism of yoga as dangerous. She looked at emergency room visits in the U S finding that per capita involved in the activity golf was more dangerous than weightlifting and weightlifting was more dangerous than yoga.
01:36:02
Speaker
End quote. Again, The main topic here is does yoga build bone? Fishman introduces another red herring by saying that weightlifting is more dangerous than yoga. So again, we're getting this appeal to emotion, right? This fear that you could hurt yourself with weightlifting, but research shows that weightlifting is as safe or safer than most sports and is no more dangerous than any other recreational exercise. So again, while yoga does not deserve a bad rap when it comes to safety, that does not mean it's effective for building bone.
01:36:31
Speaker
Okay, back to the email. He writes, quote, overall, I think your, quote, negative infomercial is regrettable in that the older population might be discouraged from doing something helpful and safe, unquote.
01:36:48
Speaker
Okay. However, our message, again, I'll say it, isn't that yoga is unhelpful and unsafe. That has never been our message.
01:37:02
Speaker
Our message, one more time for the people in the back, is that yoga doesn't build bone. It's not an osteogenic form of exercise. Yeah. And and again, this this use of the word regrettable, right? Another appeal to emotion. It suggests that he thinks we should regret what we've done, right?
01:37:20
Speaker
It's so almost like an attempt to shame us about our work. But again, just like Laurel just said, we have never said that yoga is a bad or dangerous activity. In our opinion, continuing to promote yoga as a viable, proven, effective intervention for bone density growth is actually far more dangerous. And more regrettable.
01:37:39
Speaker
You are fear-mongering weightlifting. which is along with impact training, the only proven intervention for bone density.
01:37:48
Speaker
This is anecdotal, but we mentioned it before. We have had a lot of people reach out to tell us that they thought yoga was enough for their bone building and they did yoga and now they have osteoporosis.
01:37:59
Speaker
So it's not helpful to tell people to do yoga for their osteoporosis. Just like it's not helpful to tell a marathoner trying to PR their race to just stick with strength training.
01:38:15
Speaker
Yeah. The difference between those two those two groups, though, are that there are real health consequences when someone takes on an activity that they think will improve their health when it doesn't, and there's no evidence to such suggest that it does.
01:38:30
Speaker
The stakes are a bit higher in that case. Yes, much higher.
01:38:35
Speaker
All right Going back to the email, we're a few months from completing a study to find out which poses help which bone. I'm just gonna stop for a second and say, gonna be real curious to read that because if 40 years ago, if they had to put pins in bones to figure it out,
01:38:53
Speaker
I'm very curious to see the methodology that is going to allow them to see which poses help which bones, assuming that any, sorry, I just banged into something cause I got so excited. Assuming that any change is even possibly occurring, right? Which, okay. Anyway, going back to the email, the second edition of yoga for osteoporosis is coming out in March with a discussion of bone muscle crosstalk and other contemporary issues.
01:39:20
Speaker
end quote. I mean, so Laurel and I are obviously 100% going to do a future episode on this. The insinuation that a specific pose is going to help a specific bone when none of the poses do anything strikes me as unhelpful.
01:39:37
Speaker
We would be better off, I think, with some sort of redo of his original study with all of the issues, right? Adding a control group, adding randomization, getting rid of all these confounders,
01:39:49
Speaker
If those were all addressed and they did a redo of the original study, I think that would be a more valuable way to spend time. But that's that's my opinion. And he goes on to say, quote, please understand, just as not all weightlifting will build bone, not all yoga will either.
01:40:03
Speaker
What we advocate and teach is that working diligently and daily to perfect these 12 poses, and then he says, and special challenging ones for people who are, quote, too good at the poses and don't need to work, will build bone.
01:40:18
Speaker
I don't understand. That's just a, I quite understand. think he means like providing progressions or scaling the difficulty of the pose for people who are quote, advanced or too good or. The part where it says don't need to work.
01:40:32
Speaker
I don't know what that means. Oh, I think what he means is like for students for whom the poses no longer feel challenging and they don't feel like they're working enough in the poses. Oh, okay.
01:40:42
Speaker
Trying real hard. Yeah. They, they, they are going to be provided with special challenging ones. Okay. ah I mean, even if we're, if we're just benefited the doubting and saying that yoga can build bone already, if you're suddenly, this is like, this is not part of your original study, right? Like,
01:41:02
Speaker
Anyway, I'm not going to go down that rabbit hole. Okay. Since go back to the email, since we were looking at 20 year increments and not everybody got their subsequent DEXA scans exactly 24 months after the first one, we measured by gain per month.
01:41:14
Speaker
Now we talked previously about how perfecting the poses is not a scientific approach and having to create special challenging ones is also not a scientific approach. But more importantly, I, when I first read this, I thought he was saying yoga can build bone. If we look at it in 20 year increments.
01:41:31
Speaker
Right. Is that what you understood from that sentence, Laurel? When he says, since we were looking at 20 year increments and not everyone got their subsequent DEXA scans exactly 24 months after the first one, we measured by gain per month. have no idea, but yeah, go ahead and follow through with your train of logic.
01:41:45
Speaker
Yes, because so at first that's what I thought he meant. And I was like, that is no kind of timeline for anybody. Especially if you're 65. Yeah, exactly. But on reflection, I think this is actually a typo. It makes much more sense if he's saying two-year increments, because that's how often people are getting the DEXA scans.
01:41:59
Speaker
Yeah. That's a pretty gnarly typo, though. Yeah. um And, ah you know, some people have a harder time with with writing than others. and i'm And I'm not trying to say anything about anybody's ease with writing, but there were a lot of typos. There were a lot of sentences that were hard to parse in his emails.
01:42:19
Speaker
Yes. Also, this is his reasoning, right, for using that unusual statistical analysis that I mentioned earlier, the bone mineral density gain per month divided by the confidence interval, right? I don't know.
01:42:33
Speaker
I am not a researcher, that much we know. But it seems to me that if your data is so spread out in so many ways, right, there's so many elements that were different for people, whether it was no initial DEXA, were they fully compliant?
01:42:47
Speaker
When did they get the follow-up? If all of the data is so spread out that you can't use standard statistical analysis, it seems to me that the bigger issue is perhaps the way the study was set up.
01:43:00
Speaker
Yeah. Yep. Okay, so, you know, back to your previous quote that you shared from the email, he writes, please understand, just as not all weightlifting will build bone, not all yoga will either. Okay.
01:43:19
Speaker
What I'm hearing here, but it's true, right? Not all weightlifting will build bone, not all yoga will either. That on its face seems like a true statement. But if you look a little closer, what's happening here is that he he's drawing a comparison between yoga and weightlifting and trying to put them on equal playing field here, right? This is what's called a false comparison, okay? He's drawing a false comparison between yoga and weightlifting by stating, quote, just as not all weightlifting will build bone, not all yoga will either.
01:43:45
Speaker
That's true. It's true that not all weightlifting routines are optimized for bone building. Weightlifting inherently though, has the capacity to generate the high magnitude loads required to stimulate bone adaptation according to the mechanostat model.
01:44:00
Speaker
Right? We talked about the mechanostat model. Why activities like weightlifting, jumping, impact sports generate forces that surpass a bone's threshold leading to increased bone density. And also why then low impact, low intensity activities like yoga and walking and Pilates generally do not generate sufficient strain to trigger bone building.
01:44:17
Speaker
Okay? Okay. It's helpful to think of these different zones of loading for understanding what what does trigger ah response from bone, okay?
01:44:28
Speaker
So he's trying to put them on equal playing field, okay? But let's think about these four zones of loading, okay? We've got the disuse zone. Low or no mechanical loading leads to bone loss.
01:44:39
Speaker
Yes, you're put on bed rest. Yes, you're an astronaut in outer space. This is the disuse zone, okay? Then we've got the physiological zone. Normal daily activities maintain bone but don't stimulate growth. Okay.
01:44:56
Speaker
Then we have the overload zone. High enough forces. such as what we could experience in weightlifting and plyometrics, stimulate bone formation, okay?
01:45:09
Speaker
And then we have the fracture zone. The fracture zone is when actually we've applied excessive forces that can cause bones to fracture, bones to become damaged.
01:45:20
Speaker
So while Fishman is saying, listen, not all weightlifting will build bone, not all yoga will either, He's creating a false comparison because yoga likely exists mostly in this physiological zone.
01:45:39
Speaker
That was the second one I mentioned. It's about as much force as walking as standing. It's body weight. It's what we're carrying around with us all day long. It's normal daily activity type forces that will certainly, yoga will certainly go a long way toward maintaining bone, but it's not going to stimulate bone growth.
01:45:58
Speaker
Okay? Versus heavy resistance training and impact training, which likely exists in that overload zone, where the forces now are high enough to stimulate bone formation. See, they are not equals.
01:46:10
Speaker
In this case, when we're talking about forces, they're not equals. Yet, Fishman's comparison seems to imply that they are, that they're on equal footing. And that while, you know, it's true that yoga doesn't always build bone, it's true for strength training too.
01:46:25
Speaker
The bone building effects of weightlifting are... in contrast to yoga, contingent on how it's practiced, meaning contingent on the loads that you're lifting.
01:46:40
Speaker
It's contingent on load percentage. If the loads are light to moderate, it's probably not going to be as bone building as if the loads are heavy. The bone building effects of yoga are not actually contingent on how it's practiced.
01:46:54
Speaker
This is because yoga asana, the forces that you experience in yoga yoga asana, will simply not cross the threshold they need to to take you into that zone you need to be in to experience bone formation.
01:47:09
Speaker
It doesn't matter how well you do the pose. It doesn't matter how hard you try, right? Like his teacher gets them to, quote, try hard. It doesn't matter. You're still only ever working with a limited amount of resistance in the form of body weight.
01:47:26
Speaker
Fishman also claims that for those who are, quote, too good at yoga, which we're a little confused about, I think what he's suggesting is that more challenging variations of the poses are required to continue progressing the load to build bone.
01:47:38
Speaker
And we're confused about what this word too good at yoga means. And here's why we would be confused, because what metric do we use to measure when someone is, quote, too good and needs a yoga pose that is more challenging?
01:47:51
Speaker
Okay, what metric, what number, how are we quantifying this? Is it an amount of time the pose can be held? Is it some other quantifiable parameter that can be measured? It's unclear.
01:48:03
Speaker
When I taught yoga for many years, I still do teach it occasionally. Typically in yoga, making a pose more challenging often means increasing the range of motion required in it or decreasing the base of support to make it challenge or balance more or holding it for longer to promote more of a strength endurance stimulus.
01:48:24
Speaker
We don't typically add load to yoga. You can make it so that a pose allows your body to experience more load simply by manipulating the body's position, relative to the the axis of gravity or lengthening levers. But again, you're only ever going to be using body weight to do that.
01:48:40
Speaker
This is very different than in resistance training. And another reason why we cannot actually put them on equal footing when it comes to a discussion around which one is more osteogenic, because actually in resistance training, it's crystal clear when someone is ready to progress or when they have become, quote, too good for a particular amount of load in an exercise.
01:49:00
Speaker
We know that this is the case when the weight they are lifting for a given number of reps through a given range of motion becomes easier for them, meaning they demonstrate that they are capable of lifting an amount of weight through a defined range of motion for given number of reps to the point where they begin to, for example, be able to do many more reps than what is prescribed.
01:49:22
Speaker
If it was 100 pounds for 5 reps, but then it becomes 100 pounds for 8 reps, they are now ready for a load increase, probably in the form of about 5 pounds.
01:49:33
Speaker
So this is very objective. This is quantifiable. We know when they are, quote, too good. It's through this process, unlike the process undergone for increasing challenge in yoga, that we ensure that the mechanical strain on bones remains sufficient.
01:49:48
Speaker
And we ensure that the challenge to the muscles remains sufficient to stimulate increased adaptations to to strength, right, in case of bones, bone mineral density.
01:50:00
Speaker
Okay, so they're not the same. And this is a crucial distinction that I think Fishman's argument overlooks. And it's why yoga and strength and training are not on equal footing.
01:50:11
Speaker
And so if strength training fails to build bone, we would be able to look at specific parameters, like how much load is the person being asked to lift, what exercises have been selected for the person to progressively overload? Are these the exercises that will target the specific remodeling that we're looking for, right? If we're looking for wrist bone strength improvements, we're probably not going to give them exercises that don't load the wrists in some meaningful way, right?
01:50:40
Speaker
We can also look at volume. How much strength training are they doing throughout the week? and And how are we divvying this up with regards to exercise frequency? How how often are they training?
01:50:52
Speaker
Contrast that with yoga. If yoga fails to build bone, it's because yoga is low-intensity exercise. And according to plenty of quality research, low-intensity exercise does not meet the biomechanical requirements for bone. So yes, Dr. Fishman, while it's true that just as not all weightlifting will build bone, not all yoga will either,
01:51:15
Speaker
We have a much better idea of what we can do in the weightlifting intervention to make it more osteogenic. Contrast that with yoga, whereas the only thing we can do is choose a better exercise intervention for bone building.
01:51:31
Speaker
Word.
01:51:34
Speaker
Okay. We've been talking about this for and quite a while. i have some concluding thoughts.
01:51:44
Speaker
One thing to note is that Dr. Fishman funded this study. It says so in the paper, and it says the authors declared no conflict of interest.
01:51:55
Speaker
I think it's very hard. to really have no conflict of interest when you self-fund a study about a movement modality that you are deeply invested in and have spent, at this point, 20 years of your life working on.
01:52:10
Speaker
I think it would take someone of superhuman personal character to spend that much time on something and not, in some way or another, have your desire influence the outcome. That's my take. But here's my sort of like conclusive thoughts around this. and And Laurel and I have said this before. If the research truly supported the argument that yoga builds bone, I would be on the yoga bone train.

Evaluating Credibility of Health Claims

01:52:32
Speaker
100%. We would be running a course all about yoga for bone building. We would. Laurel and I have said this before. We go by what the current evidence shows.
01:52:41
Speaker
And if there's some future study that proves... I don't know that ice skating is the best way to build bone. You'd better fucking believe that Laurel and I are going to go figure out how to teach people to ice skate.
01:52:53
Speaker
It's true. I mean, it's going to be very hard. Listen, I think, I think ice skating probably does have some osteogenic value. If you can jump up in the air and land. That's level two of our course. The first level is like, can you just not fall over?
01:53:09
Speaker
But my point is we would change our course to something else. If that's what the research showed, we wouldn't deny the research and keep pushing our course as the way to build bone. We are out here trying to be as scientifically literate as we possibly can and to help you do the same.
01:53:24
Speaker
And that's it.
01:53:27
Speaker
All right. Well, we did it. We did it. We hope you are left thinking about answers to some of our questions.
01:53:39
Speaker
Not just in your evaluation of Dr. Fishman's claims about yoga and bone building, but in your evaluation of health and fitness claims more broadly. right What makes a claim about health and exercise scientifically credible?
01:53:55
Speaker
What type of evidence should we expect before accepting a claim as fact? A single paper? No, that is not enough. The quality of the papers you're looking at matters.
01:54:11
Speaker
Are we being asked to accept conclusions that go beyond the evidence? Right? So if a study does not control for key variables, can we use that study to confidently claim that the intervention caused the result?
01:54:26
Speaker
What does it mean when someone shifts the argument instead of addressing the central critique? How does emotional rhetoric, rather than data, shape what we believe to be true?
01:54:43
Speaker
If a treatment or exercise truly worked as claimed, wouldn't we see a stronger, more consistent body of evidence supporting it?
01:54:55
Speaker
For example, why do the most well-supported interventions for osteoporosis, high-load resistance training, and impact training show clear, reproducible results across multiple studies, while Fishman's claims rely on a single, uncontrolled study.
01:55:13
Speaker
How do we push back against misinformation when it comes from someone with credentials? When it comes from someone with credentials who is an insider within a community we are a part of?
01:55:28
Speaker
In this case, we have a doctor who is well-known in the yoga community. How can we advocate for evidence-based practices without being dismissed as, quote, close-minded or, quote, anti-yoga?
01:55:44
Speaker
What responsibility do doctors and researchers have when communicating findings to the public?
01:55:52
Speaker
And here's one.
01:55:55
Speaker
If yoga truly imposed forces strong enough to stimulate osteogenesis, Wouldn't we see reports of bone stress injuries among long-term practitioners?
01:56:07
Speaker
That is an excellent, excellent point. High impact and high load training create bone growth, but they also carry risks. Stress fractures in gymnasts and runners are very common.
01:56:22
Speaker
If yoga imposed comparable load, wouldn't we see similar outcomes?
01:56:28
Speaker
All right. All right. As always, thanks for listening. Rate, review, and subscribe. Don't forget to get on the wait list for Bone Density Course Lift for Longevity. We are starting in May.
01:56:42
Speaker
May 15th. We're going to close with a song. Sorry, it sounded like church all of a sudden. It is Bob Dylan. Well, that's church for a lot of people.
01:56:53
Speaker
Come gather round people wherever you um And admit that the waters around you have grown. And accept it that soon you'll be drenched to the bone.
01:57:06
Speaker
If your time to is worth saving. you better start swimming. you'll sink like a stone. the bones, they aren't a-changing.
01:57:19
Speaker
I added that. And we will see you in two weeks.