Improve performance, body composition, and long-term health


In this episode of the Flex Diet Podcast, I sit down with Dr. Nathan Jenkins to discuss how to improve performance, body composition, and long-term health through the lens of aerobic development and metabolic flexibility.

Nathan shares his journey from exercise physiology and coaching CrossFit athletes to his new role teaching physiology at the University of Georgia School of Medicine.

We discuss why metabolic flexibility is such a powerful framework for understanding everything from biochemistry and exercise performance to metabolic disease.

We also dive into interpreting maximal exercise testing data, including VO₂ measurements, EKG analysis, and near-infrared spectroscopy (NIRS), along with how different energy systems work together during training and competition.

Dr Nathan explains why building an aerobic base is critical for repeated high-intensity performance, how pacing impacts outcomes, and why the ability to “suffer” is actually a trainable skill.

We also cover practical strategies you can apply right away, including prioritizing protein and carbohydrates, improving sleep quality, and addressing common micronutrient deficiencies through blood work, such as magnesium, vitamin D, and omega-3 status.

Better Body Comp, Performance & Health << details here

Episode Chapters:

  • 02:47 Meet Dr Nathan Jenkins
  • 04:38 CrossFit Nutrition Reality Check
  • 07:09 Leaving Tenure for Family
  • 09:21 Back to Academia and Med Ed
  • 11:29 Why Exercise Physiology Matters
  • 14:36 Stress Tests Reveal Pathology
  • 18:19 Max Testing and NIRS Setup
  • 22:42 Raw Data Over Machine Outputs
  • 24:18 Bohr Effect and Oxygen Delivery
  • 28:09 Energy Systems in the Real World
  • 33:05 Coaching Basics That Matter
  • 35:40 Teaching Cardio From First Principles
  • 36:36 Aerobic Base Reality Check
  • 37:19 Cardio for Meatheads Pitch
  • 39:13 CrossFit Endurance Breakthroughs
  • 41:49 Fixing Time Domain Weakness
  • 45:46 Pacing Like Froning Fraser
  • 48:42 RAAM Gamesmanship Story
  • 51:45 Pain Management Truths
  • 53:23 VO2 Max Feels the Same
  • 55:54 Suffering as a Skill
  • 59:09 Cold Plunge Mindset Study
  • 01:00:52 Caffeine Placebo and Belief
  • 01:03:22 Heat Acclimation and 10K Prep
  • 01:04:36 Metabolic Flexibility Lens
  • 01:08:16 Teaching Diabetes Integration
  • 01:10:56 Bloodwork Meets Flexibility
  • 01:12:37 Where Fat Goes Wrong
  • 01:15:07 Sustainable Deficit Strategy
  • 01:16:34 Four Priorities Blueprint
  • 01:17:21 Protein and Carb Targets
  • 01:21:08 Sleep and Micronutrients
  • 01:27:06 Omega-3 Testing Nuance
  • 01:29:36 Wrap Up and Next Steps
  • 01:31:52 Newsletter and Flex Diet Cert
  • 01:33:20 Final Thanks and Subscribe

If you prefer to watch the podcast, check it out below:

Better Body Comp, Performance & Health << watch here

Much love,
Dr Mike

_____________________

Mike T Nelson CISSN, CSCS, MSME, PhD
Associate Professor, Carrick Institute
Owner, Extreme Human Performance, LLC
Editorial Board Member, STRONG Fitness Mag

Mike T Nelson is a PhD and not a physician or registered dietitian. The contents of this email should not be taken as medical advice. It is not intended to diagnose, treat, cure, or prevent any health problem - nor is it intended to replace the advice of a physician. Always consult your physician or qualified health professional on any matters regarding your health.

..

Dr Mike T Nelson

Creator of the Flex Diet Cert & Phys Flex Cert, CSCS, CISSN, Assoc Professor, kiteboarder, lifter of odd objects, metal music lover. >>>>Sign up to my daily FREE Fitness Insider newsletter below

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