Flex Diet Podcast

Can you really build more muscle just by rethinking how you dose leucine and essential amino acids? Dr. Daniel A. Traylor, Ph.D. — co-founder and principal scientist of LEUVATE™ — reveals the science behind protein quality, muscle protein synthesis, and why older adults may need twice the protein dose to get the same results as younger people.

We dig into mTORC1 signaling, sarcopenia, the 30g protein absorption myth, GLP-1 drug effects on muscle, and the clinical trial data behind LEUVATE™. If you care about muscle, longevity, or protein strategy, this one is loaded.

Guest Bio

Daniel A. Traylor, Ph.D. is an Assistant Professor of Health Sciences at DePaul University in Chicago and Owner, Co-Founder, and Principal Scientist of LEUVATE™. His research explores how protein quality, amino acids, and exercise interact to influence muscle adaptation, recovery, and physical function across the lifespan. He is the co-inventor of LEUVATE™ — a precision-engineered leucine-enriched nutritional formula validated across multiple peer-reviewed human clinical trials.

Timestamps

3:36 — Can you really only absorb 30g protein at once?

9:16 — Sarcopenia: the muscle-loss crisis in aging

16:01 — mTORC1 and what triggers muscle protein synthesis

20:46 — Why older adults may need twice the protein dose

30:26 — The origin story of LEUVATE™

34:01 — Leucine: the master switch for MPS

37:56 — How leucine acts as a dimmer on mTORC1

53:21 — GLP-1 drugs, muscle loss, and amino acid needs

1:06:36 — LEUVATE™ vs whey: MPS data and ongoing trials

1:17:01 — How leucine-enriched EAAs signal differently in the gut

1:27:11 — Protein spiking and supplement quality red flags

Resources

LEUVATE™

Dr. Traylor email

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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.

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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

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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

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Dr. Emily Dow, PhD, RD, is a researcher and registered dietitian working at the intersection of nutrition, resistance training, and gut health.

Does vinegar actually do anything for your gut or your blood sugar? Can you trust a $200 mail-in microbiome test? Emily built her dissertation around questions like these, and her honest answers are a lot more useful than the marketing.

Expect to learn what a 12-week resistance-training-plus-vinegar protocol did (and didn't do) to gut permeability, why a null result in a healthy population is still worth your attention, what the research really says about vinegar and glucose control, why the peptide boom warrants a hard dose of skepticism, what direct-to-consumer gut testing genuinely can and can't tell you, the underrated role stress plays in GI symptoms, and why the best practitioners do both research and hands-on coaching — and much more.

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Connect with Dr. Dow: Website: https://www.dremilydow.com Instagram: https://www.instagram.com/dremilydow

Episodes you'll enjoy next: #127 — The Effect of Antibiotics on Muscle Mass & Cardiovascular Performance with Dr. Sara Campbell: https://flex-diet-podcast.simplecast.com/episodes/episode-127-the-effect-of-antibiotics-on-muscle-mass-aerobic-cardiovascular-performance-and-more-an-interview-with-dr-sara-campbell
 #222 — Nutrition, Supplements & Training with RD Sean Casey https://flex-diet-podcast.simplecast.com/episodes/episode-222-expert-insights-on-nutrition-supplements-and-training-with-registered-dietician-sean-casey

Enjoying the show? Follow the Flex Diet Podcast in your podcast app so new episodes land automatically — it's the single best way to help others find it.

Timeline 

0:00 Intro

02:29 Vinegar Research Origins 

04:12 Study Design & Training Protocol

07:42 Biodex Explained: Strength Testing 

11:49 Research Tradeoffs & Null Results 

14:49 Possible Mechanisms: Acetate 

19:55 Glycemic Control & CGM Findings 

22:21 Peptides: Hype and Risks 

28:54 Microbiome & Performance Research

30:47 Gut Testing Skepticism 

36:23 Stress and GI Symptoms 

39:22 PhD to RD Fast Track 

41:04 RD Exam Reality Check 

44:25 Scope of Practice Basics 

45:56 Referral Networks That Work 

49:29 Research vs. Coaching Gap 

58:51 Clients Drive Better Questions 

01:05:26 Why She Started Instagram 

01:09:58 Social Media for Academia 

01:13:18 Training Goals and Tattoos 

01:15:45 Where to Follow & Wrap Up

 

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