In this solo episode, Dr. Mike T. Nelson introduces the concept of coaching leverage—the idea that effective coaching means multiplying physiological impact by a client's realistic ability to change.

• Why sleep is a physiological powerhouse but a coaching nightmare
• The coaching leverage formula: physiology × psychology
• Why protein ranks #1 (score: 81) and sleep ranks #8 (score: 20)
• How to stop majoring in the minors with your clients
• The eight interventions inside the Flex Diet Certification
• Why following a proven system beats reinventing the wheel

The Flex Diet Certification closes tonight (Monday, June 22, 2026) at midnight Pacific. Get details here.

Get the Daily Fitness Insider newsletter (free): https://www.miketnelson.com/newsletter

In this episode of the Flex Diet Podcast, I sit down with Dr. Sara Campbell, Ph.D., Associate Professor at Rutgers University, for a conversation about the bidirectional relationship between exercise and the gut microbiome.

Dr. Sara Campbell returns to discuss her lab's cutting-edge research on the bidirectional relationship between exercise and the gut microbiome — including why consumer gut tests oversimplify a complex ecosystem, how antibiotics devastate exercise capacity in animal models, and why single-microbe probiotics miss the bigger picture of functional guilds. She also shares new findings on short-chain fatty acids, amino acid metabolomics after antibiotic treatment, and the emerging neuromuscular junction hypothesis.

In this episode you'll learn:

• Why consumer gut microbiome tests are misleading and what functional guilds tell us instead
• How antibiotics devastate exercise capacity and the surprising metabolomic changes they cause
• The current evidence on probiotics for exercise performance and why single strains fall short
• What short-chain fatty acids do for gut health and exercise, and the emerging neuromuscular junction hypothesis

Find Sara here:
Rutgers Faculty Page
Google Scholar: Sara Chelland Campbell

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The Flex Diet Podcast is brought to you by the Flex Diet Certification. Learn more at miketnelson.com

Get the Daily Fitness Insider newsletter (free): https://www.miketnelson.com/newsletter

In this solo episode, Dr. Mike T. Nelson dives into the intersection of AI and coaching. Using his quest to pick up the 175-pound Inch dumbbell as an example, he shows how AI struggles with niche topics where quality training data is scarce — and why that matters for fitness advice.

Topics covered:

• Why AI gave terrible advice on training for the Inch dumbbell — and what that reveals about how AI sources information
• The protein-and-kidney-damage myth: when AI repeats bad science
• Where AI actually helps coaches: data analysis, blood work organization, backend tasks, and production workflows
• Why clients still want (and need) a real human coach — accountability, customization, and skin in the game
• Will people be compliant to a robot coach? Probably not
• The baseline is rising: why just writing training and nutrition programs isn't enough anymore

Flex Diet Certification — now open through Monday, June 22nd, 2026 at midnight PST. Eight interventions (protein, fats, carbs, exercise, sleep, micronutrition, fasting, and more) built on coaching leverage and metabolic flexibility. Includes direct email access to Dr. Nelson for enrolled students.

Enroll now: https://miket.me/fdc

Get the Daily Fitness Insider newsletter (free): https://www.miketnelson.com/newsletter