In this episode of the Flex Diet Podcast, I’m joined by my good friend Dr. Eric Trexler, exercise scientist, educator, and Director of Education at Stronger by Science, for a wide-ranging, no-BS conversation on what physiology actually looks like in the real world.

We dig into beetroot juice, nitric oxide, and “pump” supplements, why the blood-flow story is usually oversold, and why neuromuscular function and calcium handling may matter far more than chasing a swollen muscle. We also talk about why most supplement mechanisms sound great on paper… and quietly fall apart once you look at healthy humans who already function pretty well.

From there, the conversation expands into human variability, elite athletic outliers, and why normal distributions actually guarantee that “freaks” exist — whether people are comfortable admitting it or not. We also unpack NEAT, energy expenditure, and why exercise doesn’t scale linearly for fat loss, including how the body aggressively manages its energy budget when stress or activity gets too high.

If you care about performance, body composition, or just understanding how the human system really works, this episode will recalibrate a lot of assumptions.

Sponsors:

• LMNT: http://drinklmnt.com/mikenelson (automatically applied at checkout)
• Fitness Insider Newsletter: https://miketnelson.com/
• Shiftwave: https://shiftwave.co/drmiketnelson

Episode Chapters:

• 05:01 Diving into Beet Root and Nitrate Research
• 05:58 Mechanisms and Effects of Nitrate Supplements
• 10:14 Challenges and Insights in Supplement Research
• 34:19 Elite Athletes and Physiological Variability
• 43:16 Debating the Value of Outliers in Research
• 44:38 The Importance of Studying Rare Genetic Conditions
• 45:46 Challenges in Grant Writing for Rare Conditions
• 47:39 Blood Flow and Muscle Performance
• 49:14 The Science Behind Muscle Pumps and Hypertrophy
• 56:09 Energy Expenditure and Physical Activity
• 58:02 The Non-Linear Relationship Between Activity and Energy Intake
• 01:01:28 Exercise, Appetite, and Weight Management
• 01:14:19 Balancing Cardio and Strength Training for Optimal Health
• 01:21:14 Closing Remarks and Resources

Episodes You Might Enjoy:

• Episode 352: Dr. Dan Pardi on Stem Cells, Supplements, and the Future of Health with Qualia
  • YouTube: https://youtu.be/8EZcHy_7wK8?si=aNGzT-abP9xbc6yU
• Episode 343: Fueling the Corporate Athlete: Stress, Supplements & Performance with Dan Hunter
  • YouTube: https://youtu.be/0ek4XSs62RQ?si=czR_7q96jJDqXzcF

Connect with Eric:

• Instagram: https://www.instagram.com/trexlerfitness

Get In Touch with Dr Mike:

• Instagram: https://www.instagram.com/drmiketnelson/
• YouTube: https://www.youtube.com/channel/UCn1aTbQqHglfNrENPm0GTpg
• Email: https://miketnelson.com/contact-us/

In this episode of the Flex Diet Podcast, I sit down with Dr. Jeremy Bettle, a performance director and applied sports scientist, to dig into what actually moves the needle for performance, recovery, and long-term resilience.

We cover everything from high ankle sprains and injury prevention to smarter load management, and why understanding stress, recovery, and tissue capacity matters far more than chasing random training trends.

Dr. Bettle shares insights from years of work across the NHL, NBA, and international sport, along with how elite performance systems can — and should — be translated to non-elite humans who want to train hard, recover better, and keep doing this for decades.

Sponsors:

• Rogue: https://miket.me/rogue
• Beyond Power Voltra 1: https://www.beyond-power.com/michael13
• Fitness Insider Newsletter: https://miketnelson.com/

Episode Chapters:

• 05:26 Discussion Kickoff: Injury Prevention and Load Management
• 06:10 High Ankle Sprains in Professional Sports
• 15:07 Load Management Strategies and Challenges
• 38:11 Eccentric Training and Injury Prevention
• 46:23 Muscular vs. Soft Tissue Injuries in Athletes
• 47:49 Importance of Plyometric Work in Injury Prevention
• 51:43 Isometric Exercises and Their Benefits
• 58:12 Recovery Strategies and Their Effectiveness
• 01:08:02 The Role of Communication in Team Sports
• 01:15:55 Systematizing Athlete Routines for Optimal Performance
• 01:22:52 Conclusion and Final Thoughts

Episodes You Might Enjoy:

• Episode 314: Unlocking Performance & Recovery: IV Therapies & Hyperbaric Oxygen Therapy with Jordyn Payne
  • YouTube: https://youtu.be/qnJHcepDx1c?si=aTlDcFS6D77jq49D
• Episode 325: The Uncommon Science of Cold: Brown Fat, Resilience & Recovery with Dr. Thomas Seager
  • YouTube: https://youtu.be/5ycoVRnLTuY?si=m-pgtYkkMcQhPUXJ

Connect with Jeremy:

• Vitality Collective: https://vitality-collective.com/
• Instagram: https://www.instagram.com/VitalityCollectivePerformance

Get In Touch with Dr Mike:

• Instagram: https://www.instagram.com/drmiketnelson/
• YouTube: https://www.youtube.com/channel/UCn1aTbQqHglfNrENPm0GTpg
• Email: https://miketnelson.com/contact-us/