Steve House is joined by coaches Martin Zhor and Ben Morley for a deep dive into muscular endurance — what it is, why it matters, and how to train it. The conversation covers the critical distinction between local muscular fatigue and global cardiovascular fatigue, explaining why legs failing before lungs is the defining sign of a muscular endurance deficit. Drawing on examples from ultra running, mountaineering, ski touring, and cross-country skiing, the coaches walk through the physiological mechanisms at work: muscle fiber adaptation, capillarization, metabolic efficiency, and the role of stabilizer muscles in maintaining movement quality under load.

The episode then turns practical, covering how to sequence muscular endurance training within a broader periodization plan — including the importance of building a strength and aerobic base first, how to use the 10% aerobic-to-anaerobic threshold rule as a readiness gauge, and what both gym-based and outdoor heavy-pack sessions should look and feel like. Martin and Ben also address common mistakes athletes make, from loading up on easy long hikes to skipping the downhill component entirely, and explain why this type of training is essential for anyone taking on objectives like Denali, UTMB, or long days in the mountains.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Muscular Endurance Training with Uphill Athlete Coaches

Longtime friend Kyle Lefkoff — alpinist and venture capitalist — turns the tables on host Steve House in a wide-ranging reflective conversation facilitated by producer Jamie Lyko. We are deeply grateful to Kyle for joining us: his rare combination of elite climbing experience and high-stakes business acumen made him the ideal interlocutor to draw out the season's most resonant themes.  The conversation moves fluidly between the episodes of Season 2, distilling through-lines that span risk tolerance, the explorer's mindset, delayed gratification, childhood intensity, and what it means to successfully "make the turn" from elite athletic performance to a life of purpose and contribution.  Steve reflects candidly on his own transition: the accident on Mount Temple in 2010 that forced a reckoning, the decision during COVID to cut the safety net of professional climbing income and go all-in on Uphill Athlete, and the parallel between committing on a big alpine route and committing to a business. Kyle offers a venture capitalist's lens on these same themes — examining how mountain guides develop a risk management fluency that translates directly to high-stakes decision-making in business, and how figures like Greg Penner embody the qualities of deep listening, disciplined time management, and talent recognition that define elite leaders in any arena.  The episode closes on an intimate note — three fathers of six boys between them — reflecting on how the intensity that set them apart in the mountains is something they now seek to pass on, not as a liability, but as the seed of something extraordinary. 

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo 

Write to us at coach@uphillathlete.com

Voice of the Mountains: Season Two Recap

Steve House sits down with Dr. Marco Altini — data scientist, physiologist, and founder of HRV4Training — for a deep-dive into one of the most misunderstood tools in endurance athletics: heart rate variability. With over 50 peer-reviewed papers to his name, Dr. Altini brings rare scientific rigor to a space crowded with oversimplified wearable metrics. The conversation opens by challenging the industry's obsession with single-number readiness scores, which Dr. Altini argues dilute nuanced physiological signals into deterministic assumptions that don't reflect the complexity of the human body.  

The episode unpacks the fundamentals of HRV — what it actually measures, why morning is the optimal measurement window for endurance athletes, and how to interpret it as a marker of stress response rather than performance capacity. Steve and Marco also cover hardware accuracy across chest straps, optical sensors, and phone cameras; HRV research at altitude; and the broader question of how biometric data should support — not replace — the athlete's own sense of feel.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Making Sense of the Data with Dr. Marco Altini

This is the full, unedited version of Steve House's conversation with Peter Metcalf — extended and running longer than the standard episode release.

Before Black Diamond Equipment became the most trusted name in mountain sports, there was Peter Metcalf: a teenager from Long Island hitchhiking to the Gunks every weekend, a dogeared copy of Mountaineering: Freedom of the Hills on his nightstand, and a conviction that the mountains were where he belonged.

In this conversation, Steve and Peter trace the full arc of that conviction — from his early apprenticeship years through a harrowing 13-day first ascent on Mount Hunter, where hallucinations, extreme cold, and frostbite tested everything he had. That experience forged a lesson Peter would call on again in 1989, when he organized a team of fellow climbers to buy bankrupt Chouinard Equipment out of collapse — using retirement savings, high-interest loans, and a shared sense of purpose — and rebuild it into Black Diamond.

What emerges is a portrait of someone who applied the logic of alpinism to every domain of his life: patient apprenticeship, commitment without a visible outcome, and the willingness to keep moving when the only way to live is forward. This is a story about climbing — and about becoming.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Voice of the Mountains: Success is Not the Summit with Peter Metcalf (Director's Cut)

In this special International Women's Month episode, host Chantelle Robitaille sits down with coach Alexa Hasman to explore what it truly means to train as a female mountain athlete. Together they walk through the physiological realities of each major life phase — from the menstrual cycle and pregnancy to postpartum recovery and menopause — not as limitations, but as distinct training phases requiring smart adaptation. Anchored by the guiding principle that "ability is the measure of permission," they challenge women to reject the noise of external opinion and cultivate a deep, data-informed understanding of their own bodies.

The conversation covers practical strategies at every stage: cycle-tracking tools and red flags to watch for; trimester-by-trimester training modifications during pregnancy; the often-overlooked realities of diastasis recti and pelvic floor recovery postpartum; and why strength training becomes non-negotiable during perimenopause and beyond. Alexa and Chantelle make a compelling case that women's athletic identity is not fixed to any single phase — it evolves — and that with the right coaching, community, and self-advocacy, female athletes can pursue big mountain goals at every age.

Understanding the Female Athlete

Coaches Chantelle and Alexa make the case that strength training is non-negotiable for female mountain athletes. They debunk the myth that lifting makes women bulky, distinguish between hypertrophy and functional strength, and walk through the three phases of strength programming: max strength, muscular endurance, and maintenance. Special attention is given to eccentric strength, an often-overlooked element critical for the downhill demands of mountaineering, trail running, and skiing. Learn how to get started as a beginner, common training mistakes, smart recovery practices, and how to measure progress beyond the weight on the bar. Get practical, accessible options for fitting strength work into a busy life. No matter your experience level or life stage, the best time to start is now.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Strength for the Female Athlete

Dr. Christine Theodorovics — Viennese-born insurance CEO, doctoral researcher, and accomplished recreational mountaineer — joins Steve House for a wide-ranging conversation about what the mountains teach us that the boardroom cannot. Christine's story spans a humble upbringing in Vienna's public housing, a near-fatal attempt on Huayna Potosí with zero acclimatization, 25 years of quietly ticking off all 48 Swiss 4,000-meter peaks alongside a demanding executive career, and doctoral research interviewing 13 expedition leaders aged 39 to 97 across eight countries. What she found surprised her: at the end of every mountaineering life, what mattered most wasn't summits — it was the human connection forged along the way.

The conversation moves fluidly between expedition leadership and corporate governance, Viktor Frankl and intrinsic motivation, quota politics and the permission women give themselves to lead. Christine argues that accountability can never be truly shared, that freedom requires a well-defined frame, and that the mountains remain one of the few places where positional authority dissolves entirely — replaced by demonstrated competence and trust earned in the field. A self-described "curious" person who has financed every step of her own path, Christine offers a perspective that is equal parts rigorous and warm, and thoroughly earned.

Voice of the Mountains: The Measure of Permission with Dr. Christine Theodorovics

In this science-focused episode, host Steve House sits down with Dr. Patrycja Jonetzko, a cardiothoracic anesthetist and high-altitude medicine expert, to explore the fundamental mechanics of gas exchange and oxygen delivery in mountain athletes. Dr. Jonetzko breaks down the journey of oxygen from atmosphere to working muscle, explaining the oxygen cascade, the critical role of partial pressure versus oxygen concentration, and why altitude performance is diffusion-limited rather than VO2 max-limited. The conversation illuminates why the body's adaptation to hypoxia is far more complex than simply producing more red blood cells.

The discussion moves beyond basic physiology into practical application, covering breathing techniques like pressure breathing, the importance of hydration for gas diffusion, and why slower, deeper breaths are more efficient at altitude than rapid shallow breathing. Dr. Jonetzko advocates for reframing "acute mountain sickness" as "altitude adaptation syndrome"—recognizing that most symptoms represent normal physiological adaptation rather than pathology. She emphasizes that while genetic factors play a significant role in altitude performance, pre-acclimatization strategies including hypoxic tents and intermittent hypoxic training can meaningfully prepare athletes for high-altitude objectives.

Drawing from both her clinical intensive care work and decades of Himalayan expedition medicine, Dr. Jonetzko reveals that success at extreme altitude ultimately comes down to energy management and self-awareness. The ability to maintain physiological efficiency while operating within narrow margins—controlling breathing rate, managing fear responses, and reading subtle body signals—often distinguishes those who summit from those who don't, regardless of baseline fitness levels.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Gas Exchange and Altitude Acclimatization with Dr Patrycja Jonetzko

In this concluding conversation, Mark Twight takes Steve into the harrowing heart of the 1988 Nanga Parbat expedition—four climbers clipped to a single ice screw, buried under avalanche debris for thirty minutes on the world's largest mountain wall. The vivid recounting reveals how total commitment to an ideal can blind climbers to approaching storms, yet paradoxically, that same commitment becomes the forge where transformation happens.

The conversation traces Mark's evolution from elite alpinist to founder of Gym Jones, where training fighters, military operators, and eventually Hollywood's Spartans became his vehicle for service. What began as "grad school for himself" shifted into duty—a way to repay the society that had given him freedom to pursue his obsessions. Through years training actors for films like 300 and Wonder Woman, Mark applied the same all-or-nothing intensity that defined his climbing, discovering that accountability to a creative partner mirrors the trust demanded on a mountain face.

When Steve asks about the through-line connecting all versions of Mark—the nihilistic Dr. Doom, the alpinist, the trainer, the writer—Mark distills it simply: chasing human potential, first for himself, then wanting it for others. The episode closes with Mark reading Bukowski's "No Leaders, Please"—a meditation on reinvention that has meant different things across different chapters of his life, now a celebration of constant growth rather than a confrontational manifesto.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Voice of the Mountains: The Responsibility to Remain with Mark Twight (part two)

In this first installment of a two-part conversation, Steve House sits down with legendary alpinist Mark Twight for one of Voice of the Mountains' most anticipated episodes. This deeply personal dialogue - the show's first in-person recording - reunites two climbers whose friendship spans more than three decades.

The conversation opens with Twight's 2019 book Refuge and his struggle to redefine himself after stepping away from elite climbing. As the 25th anniversary of their landmark Slovak Direct climb approaches, they examine what that 60-hour nonstop ascent of Denali meant then and what it reveals now about ambition, limits, and the courage to walk away.

Twight shares candidly about the costs of single-minded pursuit: failed relationships, financial instability, and the brutal honesty required to assess one's own decline. He traces his evolution from uncompromising soloist to gym owner and trainer, including his work preparing actors for films like 300and Man of Steel.

Most powerfully, Twight reflects on the deaths of friends and mentors - Mugs Stump, Jeff Lowe, Scott Backes - and the weight of survivor's guilt. He and Steve explore what it means to remain open to relationships despite knowing the potential for loss.

Part 1 ends on a cliffhanger: the setup for Twight's harrowing survival story on Nanga Parbat's Rupal Face, where four climbers hung from a single ice screw while buried by avalanche. That story continues in Part 2.

Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo [http://uphillathlete.com/letsgo]

Write to us at coach@uphillathlete.com

Voice of the Mountains: The Hunger for Redemption with Mark Twight (part one)

We educate and inspire you to be the best mountain athlete you can be with unmatched experience and proven training knowledge.

Uphill Athlete

Shows