Flex Diet Podcast

In this short Flex Diet Podcast episode, I share a reminder that the PhysFlex Surge enrollment closes Monday, April 27, 2026 at midnight PST, and I give more context on what’s inside the PhysFlex Certification. I explain how Level 1 (Flex Diet Cert) covers nutrition and recovery basics, while Level 2 (Physiologic Flexibility) focuses on becoming more robust and resilient by improving the four pillars of homeostatic regulation: temperature, pH, fuels (including ketones), and air (managing oxygen and CO2). 

I walk through my eustress vs distress model, why most interventions work better with lower intensity and higher frequency, and how misapplying tools like cold immersion, sauna, or breathing methods can backfire without the right context.

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In this episode, I sit down with respiratory and sleep scientist Martin McPhilimey to take a deep dive into breathing, CO₂ regulation, and how they actually impact performance, stress, and sleep.

We get into why respiratory physiology is way more complex than most people think, how his clinical and research background shaped his approach, and why breathwork exploded during COVID with names like Wim Hof and James Nestor.

From there, we dig into allostatic load and why piling on high-stress practices—like aggressive hyperventilation or cold exposure—can backfire if you’re already running hot. We also talk about the difference between actually relaxing your system versus just dissociating from it.

We cover how inspiratory muscle training can improve performance and recovery, why respiratory rate is one of the most sensitive markers of stress, and question some common ideas, such as “CO₂ tolerance.”

We also touch on the risks and limited data around inhaled CO₂ therapies and what actually makes sense to apply in the real world.

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In this episode, I talk about the Physiologic Flexibility Certification open from April 20 to April 27 and where to get all the details.

At the core is physiologic flexibility, which is your body’s ability to adapt, perform, and recover across different stressors, not just optimize one thing. I break down the four key systems that drive this: temperature, pH, fuels (carbs, fat, lactate, ketones), and breathing (O₂/CO₂), and how they all work together.

We also get into why AI can miss the physiology, how a 30-second Wingate hits all four pillars, and how to apply this to real-world training with 40+ practical takeaways.

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In this episode of the Flex Diet Podcast, I sit down with my good buddy Ari Whitten to talk all about red light therapy (photobiomodulation) and why it’s become so popular lately. We dig into how red and near-infrared light fits into an evolutionary sunlight context, why those wavelengths penetrate tissue differently, and how they can influence mitochondria, recovery, and performance. 

Ari also breaks down the confusing part most people miss: device choice and dosing aren’t one-size-fits-all, and “more power” isn’t always better, especially for sensitive areas like facial skin and the eyes. We also get into emerging research on sleep and melatonin (including intracellular melatonin), as well as practical considerations such as clothing and light penetration. Ari’s updated book, The Ultimate Guide to Red Light Therapy (2.0), is out now.

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In this episode of the Flex Diet Podcast, I sit down with Dr. Scott Sherr to take a deep dive into methylene blue, mitochondrial function, and where the truth lies between online hype and fear. We talk through how methylene blue acts as a redox cycler in the mitochondria, how dosing differs for mitochondrial support versus antimicrobial use, and why high doses or poorly labeled liquid droppers can cause problems. 

Dr. Sherr also shares how he’s used methylene blue with athletes for recovery and endurance, including timing, half-life, and practical ranges he sees most often. We cover how mitochondrial health connects to energy, mood, focus, stress physiology, and recovery, plus resources from Transcriptions and the Health Optimization Medicine and Practice (HOMe/HOPe) framework.

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In this episode of the Flex Diet Podcast, I sit down with Dr. Masha Makeeva, a physician specializing in integrative and regenerative medicine, to get a clear, practical breakdown of hyperbaric oxygen therapy. We talk about why HBOT’s biggest benefit may be reducing inflammation, who it can help most, and how to think about protocols — pressure, oxygen concentration, session length, frequency, and total number of sessions —so you’re not comparing totally different approaches. 

We also dig into where she sees HBOT used most (including cancer support and professional sports), why solid tumors may respond differently than blood cancers, and how HBOT can support recovery and quality of life during treatment. We cover safety, home chamber considerations, and how mitochondrial and metabolic health, HRV, and downregulation all fit into better outcomes.

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A physician buddy asked me whether the general population should focus on cardio or lifting — and I wanted to share my answer with you. In this solo cast, I break down why cardio and resistance training produce different adaptations, offer my go-to weekly framework for getting started, and talk about zone two training, high-intensity intervals, VO2 max assessments, and why compliance beats the perfect program every time. Plus, the Flexible Meathead Cardio Course is open for enrollment through Wednesday.

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In this episode of the Flex Diet Podcast, I sit down with my friend Kristi Storoschuk, a PhD candidate in exercise physiology, to unpack her review paper on zone 2 cardio and what the evidence actually shows. We dig into what “zone 2” really means (including lactate thresholds and why common proxies like heart rate and the talk test can miss the mark), where the 80/20 endurance model came from, and why messaging around zone 2 for mitochondrial function, fat oxidation, metabolic flexibility, and health may be overstated, especially for the general population. 

Kristi explains why higher intensities often produce equal or better mitochondrial and performance-related adaptations, how training volume and population context change the conversation, and where low-intensity work like walking may still fit.

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In this episode of the Flex Diet Podcast, I sit down with coach Kevin Dineen to talk about where fitness and healthcare are headed and whether their merger is a net positive or negative. We dig into why people still default to asking physicians about training and nutrition, the problems created by siloed systems, and what a more client-centered model could look like with coaches, PTs, massage therapists, and physicians collaborating under one roof. 

We also discuss the pros, cons, and liability concerns around coaches using blood work for performance, how hard training can skew lab results, and why basic habits like lifting, cardio, steps, and community support matter more than expensive supplement stacks. Kevin closes with key advice for newer coaches: professionalism, mentorship, travel to learn standards, and clarifying your “why.”

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In this episode of the Flex Diet Podcast, I sit down with Dr. Ashley Dwyer, a PharmD-turned nutrition and fitness coach, to cover a wide range of topics, with a strong focus on PCOS (polycystic ovarian syndrome), a metabolic condition that affects fertility, cycles, and systemic health. 

We dig into practical lifestyle strategies for insulin-resistant PCOS, including balanced meals, protein and fiber, blood sugar management, movement, and stress reduction, plus why long-term keto often isn’t a great fit. We also discuss GLP-1 medications, including concerns about HRV and resting heart rate, and why foundations and coaching matter when someone uses them. 

Finally, we discuss the current “wild west” of peptides, the lack of human data, dosing and purity issues, and the importance of transparency, consistency, and identity-based behavior change for body composition and long-term health.

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