Flex Diet Podcast

In this episode of the Flex Diet Podcast, I sit down with creatine researcher Dr. Darren Candow from the University of Regina to break down what the research actually says about creatine for muscle, performance, and body composition—plus the newer interest in brain health, aging, and longevity. We dig into practical dosing (including higher-dose ideas for bone and brain), why timing probably doesn’t matter much, and what the data shows on safety, side effects, and common myths like hair loss. We also talk about creatine in special contexts like sleep deprivation, jet lag, concussion/TBI potential, and vegan or low-creatine diets, along with how caffeine might (or might not) interfere. If you want an evidence-based, real-world guide to creatine, this one’s for you.

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.

In this episode, I sit down with respiratory and sleep scientist Martin McPhilimey to do a deep dive into breathing, CO₂ regulation, and how it actually impacts 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 like “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.

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.

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. Sponsors: Daily Fitness Insider Newsletter: https://flex-diet.kit.com/bfa1510fa8