• 1 hour 18 minutes
    What Vinegar & Lifting Really Do To Your Gut — Dr. Emily Dow — #388

    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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    8 June 2026, 9:00 am
  • 1 hour 33 minutes
    Episode 387: Nathan T. Jenkins on Metabolic Flexibility, Aerobic Base, and First Principles

    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. 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.

    To wrap up, we 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.

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    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

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    2 June 2026, 8:58 pm
  • 1 hour 53 minutes
    Episode 386: Nervous System Regulation, Somatics, and Stress Resilience with Tracy Holemeyer

    In this episode of the Flex Diet Podcast, I sit down with my friend Tracy Holemeyer (Uncontrollably Me, host of the Other Way to See It podcast) to talk about healing and performance through nervous system flexibility, somatics, and self-awareness, especially with how much stress people are carrying right now. 

    We dig into practical tools like orienting, grounding, the “starfish” drill, pendulation, and Tracy’s “core four” (soft eyes, relaxing the tongue, breath pacing for coherence, and soft knees), plus how posture and unconscious habits can shape mood and behavior. We also explore the value of community and coaching, how movement and sound (including humming, voo breath, and growling) can help regulate, and we finish with a thoughtful discussion on psychedelics, integration, and why support and discernment matter.

    Sponsors:

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    Episode Chapters:

    • 02:59 Meet Tracy and Catch Up
    • 04:46 Micro Breaks and Orienting
    • 08:46 Starfish and Body Awareness
    • 10:44 Joints Posture and Anxiety
    • 17:37 Strategies Become Identity
    • 21:00 Awareness Coaching in Practice
    • 26:02 Coaching Community and Support
    • 32:44 Social Media Validation Trap
    • 36:13 Integrity and Business Alignment
    • 39:39 Trauma Weight and Safety
    • 41:57 Referrals Over Scarcity
    • 43:07 Abundance Through Uncertainty
    • 47:09 Money Purpose and Access
    • 52:57 Capacity and Ongoing Stress
    • 57:15 Pendulation and Core Four
    • 01:03:00 Movement Urgency and Sound
    • 01:08:55 Growling Music and Release
    • 01:15:23 Healing as Defiance
    • 01:16:59 Flow States and Community
    • 01:18:23 Recreation With Real Stakes
    • 01:20:13 Choosing Controlled Hardship
    • 01:21:09 Healthy Stress Builds Capacity
    • 01:23:34 Rewriting Trauma Responses
    • 01:25:28 Psychedelics And Integration
    • 01:34:07 Avoiding The Healing Shortcut
    • 01:37:10 Where Memories Live
    • 01:42:45 Four Tools For Stress
    • 01:46:19 Finding Tracy And Closing
    • 01:49:45 Podcast Wrap And Disclaimer

    Flex Diet Podcasts you may enjoy:

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    27 May 2026, 1:08 am
  • 1 hour 33 minutes
    Episode 385: Rob Wilson on BJJ Performance Frameworks, Grip Training, Recovery Tech & The Check Engine Light Book

    In this episode of the Flex Diet Podcast, I sit down with human performance specialist and coach Rob Wilson for a wide-ranging conversation that spans music, coach education, and what it really means to train for performance longevity. We dig into Rob’s new book, The Check Engine Light: Tune In Your Body and Mind to Achieve Performance Longevity, and his work educating coaches through ALTIS and with special operations communities.

    Rob also shares why jiu-jitsu strength and conditioning still lacks clear performance standards and proposes building sport-specific frameworks (like lower-body clinching demands) before jumping to exercise selection. We talk grip strength vs endurance, avoiding redundancy and tendon issues, contra-specific training for durability, and why “recovery” isn’t the goal—adaptation is—especially in elite sport.

    Sponsors:

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    Episode Chapters:

    • 02:41 Nineties Music Nostalgia
    • 05:08 Seasonal Listening Habits
    • 11:17 Teaching and ALTIS Work
    • 13:25 Building BJJ Performance Frameworks
    • 22:55 Grip Strength and Tendon Tradeoffs
    • 26:51 Grip Training Hacks and Extensions
    • 37:34 Transfer, Gait, and Fuzzy Sports
    • 46:13 Compensation in Athletes and Aging
    • 51:50 Warrior Fitness Reset
    • 53:00 Check Engine Light System
    • 54:27 Spiderweb Symptoms Explained
    • 56:12 Eyes Unlock Performance
    • 57:53 Stuck in Your Box
    • 01:02:47 Logistics and Stakeholders
    • 01:06:08 Effects Over Modalities
    • 01:08:55 Recovery vs Adaptation
    • 01:15:50 Wearables Need Context
    • 01:19:41 Effort When Tired
    • 01:25:50 Cold Plunge Mindset
    • 01:30:14 Book Links and Wrap Up
    • 01:31:07 Final Thanks and Disclaimer

    Flex Diet Podcasts you may enjoy:

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    18 May 2026, 8:28 pm
  • 1 hour 14 minutes
    Episode 384: Building Strength & Muscle After 50 (Without Getting Hurt) with Chad Landers

    In this episode of the Flex Diet Podcast, I talk with my good buddy Chad Landers, veteran trainer, strength coach, and author of Building Strength and Muscle After 50, about how to keep gaining strength and muscle as you get older without falling off the “injury cliff.” We dig into why consistency matters most, how progress often drops in steps after injuries, and why smart modifications beat worshipping any single lift. 

    Chad shares lessons from coaching clients for decades, including balancing pressing with back work, using better technique (like pause benching), and building conditioning with tools like the fan bike, rower, and step mill. We also cover practical programming, tracking PRs beyond 1RM, and why it’s never “too late” to start training—especially after 50.

    Sponsors:

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    Episode Chapters:

    • 03:31 Book and Aging Strong
    • 05:21 Consistency and Injury Cliff
    • 08:52 Modify Training for Joints
    • 16:11 Bench Press Progress
    • 18:29 Bench Tips and Ego
    • 23:34 Back Work and Ratios
    • 28:38 Programming and Cardio Intervals
    • 32:17 Accountability and Habits
    • 35:59 Cardio Gear Picks
    • 37:19 Best Cardio Machines
    • 38:44 Elliptical And Zone Two
    • 39:33 Fan Bike Reality Check
    • 41:04 Cheap Bike Trainer Setup
    • 42:05 Interval Training Blueprint
    • 44:28 StepMill For Drummers
    • 46:09 Performers And Conditioning
    • 49:49 Consistency Over Supplements
    • 56:03 Why Write The Book
    • 59:56 Tracking PRs With Logs
    • 01:03:34 Coaching Hacks And Rehab
    • 01:06:39 Where To Buy The Book
    • 01:11:07 Podcast Wrap Up Disclaimer

    Flex Diet Podcasts you may enjoy:

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    Get In Touch with Dr Mike:

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    11 May 2026, 8:04 pm
  • 55 minutes 56 seconds
    Episode 383: Body Composition, Strength Training, and Sustainable Habits with Martin Silva

    In this episode of the Flex Diet Podcast, I’m on the road and sit down with strength coach Martin Silva to talk about how to improve body composition, performance, and long-term health, especially for high-achieving clients in the 35–60 range.

    We get into unlearning a lot of the nutrition beliefs people bring in, why I still like keeping nutrition simple, higher protein, fewer ultra-processed foods, and how short-term tracking can build awareness without becoming a crutch.

    Martin also walks through how he structures coaching check-ins, his own background going from bodybuilding and restriction to a more health and strength-focused approach, and what actually works in the real world. We also cover programming, including full body vs upper/lower splits, single-leg work, squat and deadlift variations (I’m a fan of the trap/hex bar here), mobility priming, and how to monitor technique even when coaching online.

    Plus, we dig into stress, sleep, managing distractions (your phone is probably not helping), and a few rapid-fire tips—including “never miss twice.”

    Sponsors:

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    Episode Chapters:

    • 02:21 Body Comp Framework
    • 04:00 Nutrition Basics Protein
    • 07:01 Adherence Tracking Habits
    • 10:21 Check Ins Coaching System
    • 13:28 Mindset Lessons Reverse Diet
    • 15:01 Bodybuilding Backstory Shift
    • 18:14 Performance First Training
    • 20:47 Programming Frequency Splits
    • 25:15 Mastering Compound Lifts
    • 27:25 Squat Alternatives Single Leg
    • 28:47 Deadlift Hinge Progressions
    • 29:54 Hip Thrust Debate
    • 30:42 Hip Thrusts for Athletes
    • 31:30 Front Loaded Squat Options
    • 33:09 Single Leg Strength Focus
    • 34:18 Z Press and Pressing Variations
    • 36:05 Mobility and Priming
    • 37:57 Trap Bar Deadlift Preference
    • 39:27 Stress and Sleep Routines
    • 43:03 Phone Distraction Strategies
    • 46:48 Four Tips for Body Comp
    • 51:52 Mindset Never Miss Twice
    • 52:43 Where to Find Martin
    • 53:26 Wrap Up and Disclaimers

    Flex Diet Podcasts you may enjoy:

    Connect with Martin:

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    5 May 2026, 9:03 pm
  • 52 minutes 40 seconds
    Episode 382: Creatine for Muscle, Bone, Brain & Longevity (Plus Caffeine, Dosing, and Safety) with Dr. Darren Candow

    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.

    Sponsors:

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    Episode Chapters:

    • 04:00 How Candow Started Creatine
    • 06:10 Glutamine Reality Check
    • 07:17 Top Supplements Today
    • 08:23 NAD Hype vs Evidence
    • 11:36 Creatine Dosing and Timing
    • 15:06 Brain Uptake and Sleep Loss
    • 18:17 Safety Diet and Essentiality
    • 21:49 Harris Studies and Dose Ranges
    • 24:30 Creatine for Concussion Prevention
    • 26:31 High Dose Game Prep
    • 27:12 Creatine Beyond Sports
    • 29:16 Soccer Cognition Hits
    • 31:38 Caffeine Creatine Myth
    • 35:11 Caffeine Dosing Timing
    • 37:32 Creatine Bone Findings
    • 39:22 Bone Research Reality
    • 43:39 Heart Health Potential
    • 44:20 Creatine Forms Hype
    • 46:30 Future Creatine Research
    • 47:51 Wrap Up Resources
    • 48:37 Conference Manual Plug
    • 51:29 Medical Disclaimer Outro

    Flex Diet Podcasts you may enjoy:

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    Get In Touch with Dr Mike:

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    29 April 2026, 8:21 pm
  • 16 minutes 23 seconds
    Episode 381: PhysFlex Cert Closing Tonight: Eustress vs Distress, the 4 Pillars, and Applying Recovery Tools the Right Way

    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.

    Episode Sponsor:

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    Episode Chapters:

    • 00:17 PhysFlex Surge Deadline
    • 01:10 Who the Cert Is For
    • 01:55 Four Pillars Overview
    • 02:31 Time Cost and Zone 2
    • 03:16 Sauna and Cold Progression
    • 04:16 Eustress Versus Distress
    • 05:01 Training Frequency Principles
    • 07:43 Course Structure Breakdown
    • 08:30 Research Meets Application
    • 09:29 Context Matters Example
    • 12:32 When Interventions Backfire
    • 14:29 Wrap Up and Reminder
    • 15:12 Medical Disclaimer

    Get In Touch with Dr Mike:

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    27 April 2026, 4:45 pm
  • 1 hour 4 minutes
    Episode 380: Breathing, CO2 Regulation, and Performance: Deep Dive with Respiratory & Sleep Scientist Martin McPhilimey

    In this episode, I sit down with respiratory and sleep scientist Martin McPhilimey to take a deep dive into breathing, CO₂ regulation, and how they actually impact 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, such as “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.

    Sponsors:

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    Episode Chapters:

    • 04:22 Why Breathing Is Complex
    • 07:52 Martin’s Origin Story
    • 11:20 From Clinics to Online
    • 14:57 Breathwork Goes Mainstream
    • 20:13 Wim Hof Risks and Load
    • 24:06 When Intense Breathwork Fits
    • 29:18 Relaxation vs Dissociation
    • 31:30 Respiratory Muscle Training
    • 35:12 Who Should Train Breathing
    • 36:35 Simple Device Protocol
    • 37:35 Why Teams Ignore Breathing
    • 38:27 Respiratory Rate as Stress
    • 39:52 Feedforward Breathing Control
    • 42:22 Rethinking CO2 Tolerance
    • 46:03 Nasal Breathing Tradeoffs
    • 48:28 Testing Limits and HRV
    • 50:48 Overnight Rate and Calm
    • 54:07 CO2 Inhalation and Risks
    • 56:45 State Encoding and Fear
    • 01:00:35 Wrap Up and Disclaimers

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    24 April 2026, 7:21 pm
  • 17 minutes 58 seconds
    Episode 379: Physiologic Flexibility Certification Open: Temperature, pH, Fuels, and Breathing for Performance

    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.

    Episode Sponsor:

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    Episode Chapters:

    • 00:19 Cert Enrollment Details
    • 01:36 AI Pitfalls and Cold Plunge Example
    • 04:05 Four Pillars Overview
    • 05:26 Breathing Module Deep Dive
    • 06:39 Homeostasis and Why It Matters
    • 07:39 Basics First Then Add Stressors
    • 08:51 Wingate Example All Systems Overlap
    • 12:05 Time Efficient Programming
    • 13:37 How to Join and Bonuses
    • 14:48 Coach as Translator and Course Structure
    • 16:22 Wrap Up and Medical Disclaimer

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    20 April 2026, 7:39 pm
  • 58 minutes 6 seconds
    Episode 378: Red Light Therapy: Sunlight, Mitochondria, Sleep, and How to Use Devices Correctly with Ari Whitten

    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:

    Coming up:

    Available now:

    Episode Chapters:

    • 04:40 Catching Up Surf Talk
    • 07:34 Sunlight vs Red Light
    • 08:50 Photobiomodulation Basics
    • 11:04 Optical Window Explained
    • 15:41 Timing and Circadian Effects
    • 19:36 Sleep and Melatonin Links
    • 26:00 Clothing and Light Penetration
    • 27:36 Red Light for Eye Health
    • 29:48 Red Light for Eyesight
    • 30:47 Dose and Panel Pitfalls
    • 31:52 Deep vs Superficial Dosing
    • 35:02 Biphasic Response and Safety
    • 38:11 Heuristics for Panel Use
    • 40:46 Choosing the Right Device
    • 42:17 Optics Distance and Angles
    • 44:39 LED Density and Hot Spots
    • 46:47 Device Examples and Timing
    • 48:31 New Book and Wrap Up
    • 53:59 Host Outro and Disclaimer 

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    13 April 2026, 7:37 pm
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