Flex Diet Podcast

Jonah Rosner is a sport scientist, performance coach, and founder of Marathon Science, translating endurance research for runners and hybrid athletes.

Does everyone really need two to three hours of Zone 2 each week? Sport scientist Jonah Rosner joins Dr. Mike T Nelson to explore when higher-intensity work makes sense, how to separate cardiovascular stress from tissue stress, and what heat training and blood flow restriction may add to an endurance plan.

Expect to learn why time-crunched lifters may benefit from carefully selected intervals, how to separate cardiovascular load from tissue load, why sprinting needs a gradual runway, what heat acclimation may change beyond plasma volume, where oxygen strategies and blood flow restriction fit, and how to interpret heart rate alongside performance, and much more.

Connect with Jonah:

Marathon Science newsletter
Instagram: @rosnerperformance

Episodes you’ll enjoy next:

VO2 Max, Zone 2 Training & the Psychology of Human Performance — Ben Skutnik — #402

From Powerlifter to Trail Runner — Paul Oneid & Cody Miller — #393

Episode Timestamps:

03:00 Zone 2 Versus HIIT
05:00 Choosing Safer HIIT Modes
08:56 Building Toward Faster Sprints
13:30 Quality Density Running Repeats
15:48 Polarizing Your Running Training
19:36 Heat Training For Endurance
26:40 Exercising In The Heat
29:48 Cooling And Heat Perception
32:27 Cold Water Between Intervals
35:10 Altitude And Oxygen Strategies
40:35 Exercise With Oxygen Therapy
42:16 Blood Flow Restriction Training
45:10 Measuring Muscle Oxygen Extraction
52:04 Heart Rate Versus Output
57:26 Triphasic Training For Runners
61:25 Thinking Beyond Training Dogma

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James de Lacey is a strength and conditioning coach with an MSc in Sport & Exercise Science and more than a decade of experience in professional sport spanning professional and international rugby/rugby league. He now focuses on combat sports to prepare fighters under Sweet Science of Fighting.

Do fighters really need zone 2 cardio? Strength and conditioning coach James de Lacey of Sweet Science of Fighting joins Dr. Mike T Nelson to challenge the "big aerobic base first" playbook for combat sports, from heart rate recovery and short-rest sprint intervals to muscle oxygen (NIRS) data. They also dig into VO2 max, wearables and why AI-written programs often miss the mark.

Expect to learn why James questions the “huge aerobic base” approach for fighters, how heart rate recovery and heart rate kinetics can reveal more than time in zones, how short-rest sprint intervals and a simple air bike baseline test can guide programming, what muscle oxygen (NIRS) data can and can’t tell you, why trends beat single data points from wearables, and why generic AI-written programs often miss the mark—and much more.

Connect with James:

• https://sweetscienceoffighting.com
• https://jamesdelacey.com
• Sweet Science of Fighting on Instagram
• Sweet Science of Fighting on YouTube

Episodes you'll enjoy next:

• Episode 326: Row Hard, Breathe Easy: Boosting Aerobic Capacity with Dr. Kenneth Jay: Dr. Kenneth Jay on rowing and boosting aerobic capacity (Mike credits Dr. Jay for the bioenergetic testing he mentions in this conversation).
• Episode 221: Training performance, nitric oxide, blood flow, and more via the NNOXX device with Evan Peikon: Evan Peikon on training performance, nitric oxide and blood flow via the NNOXX device (Mike mentions Evan in this conversation).

Episode Timestamps:

• 03:35 The biggest conditioning mistake in MMA
• 05:50 Why sprints are more aerobic than you think
• 07:46 Do fighters need a huge aerobic base?
• 09:44 VO2 max, muscle limits and oxygen testing
• 11:57 Conditioning trends and training volume
• 15:36 Zone 2, time costs and the 80/20 debate
• 22:10 Heart rate response and recovery between rounds
• 25:43 Mike’s rower test and heart rate recovery
• 28:25 Air bike sprints with short rests
• 31:44 Muscle oxygen and power between repeats
• 34:19 Testing and training each athlete’s limiter
• 41:47 Flexible Meathead Cardio and technical training
• 46:05 Elite athletes, VO2 max and training context
• 50:22 NIRS, oxygen drops and peak power
• 57:18 Why trends beat single test results
• 1:02:56 Wearables, coaching judgment and session design
• 1:06:57 AI programs and generic training blocks
• 1:13:02 Training around life and where to find James

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Bryan Krahn has been a personal trainer since 1997, a CSCS since 2005, and a full-time online coach since 2014. He is a fitness writer and the author of two books with Men's Health.

Will AI replace online coaches, or only the ones who stop being human? Veteran online coach and Men's Health author Bryan Krahn joins Dr. Mike T Nelson for a candid, unfiltered conversation about paying for expertise, whether coaches should disclose AI use, personal experiences with peptides and TRT (opinion, not advice), and Mike's simple rower-based cardio plan.

Expect to learn why paying for expertise makes you a better coach, how Bryan and Mike use (and distrust) AI in coaching and writing, whether coaches should disclose their AI use, why stacking compounds makes personal experiments hard to interpret, how Bryan thinks about TRT and lab markers like HDL, LDL and PSA, and Mike’s simple rower-based cardio plan—and much more.

Bryan and Mike discuss peptides, TRT and other compounds from personal experience and opinion. Nothing here is medical advice; talk to a qualified healthcare professional before changing any medication or supplement routine.

Connect with Bryan:

• https://over50muscle.com/
• Bryan on Instagram (@bryankrahn)

Episodes you'll enjoy next:

• Episode 137: Training Straight Talk with fitness writer, and online physique coach Bryan Krahn: Bryan's previous visit to the show: training straight talk from a fitness writer and online physique coach.
• AI Disclosure, Deepfakes & the Death of Expertise — Dean Guedo & Jeb Stuart Johnston — #404: Dean Guedo and Jeb Stuart Johnston on AI disclosure, deepfakes and the death of expertise (Mike mentions Dean in this conversation).

Episode Timestamps:

• 02:25 Online coaching's catch-22: taking clients you may not be set up to help
• 04:16 Bryan's niche: from over-40 clients to the over-50 guy, and why parents and older dads fit
• 06:10 Edge-case clients, referral networks and paying peers for expertise
• 08:06 Why paying for consults still matters, including Bryan's 1999 consult with Charles Poliquin
• 11:35 Why AI still struggles with niche training questions: PEDs, zone two and the Thomas Inch dumbbell
• 17:03 AI inside coaching software, and why chatbots are so agreeable
• 18:53 Would clients be accountable to a bot, and will live coaches last?
• 23:48 Should coaches disclose AI use to clients? Everyday AI wins like soundbars and grill repair
• 27:29 Contest-prep coaches, AI photo checks, and why coaches get second opinions
• 34:32 Peptide offers and appetite-suppressing drugs: personal experiences, not advice
• 39:38 DNP stories and risks as the speakers recount them
• 42:34 Mitochondrial peptides, NAD+ and IV infusions: why stacked self-experiments are hard to interpret
• 49:39 TRT: dialing in the basics first and working with a physician
• 52:41 Lab markers: HDL, LDL and PSA, and changing the marker versus the outcome
• 58:37 Traveling with a TRT prescription: Bryan's border-security story
• 1:01:25 Mike's rower cardio plan: baseline 2K test, progressive six-minute sessions and a smarter four-by-four
• 1:10:58 Should writers disclose AI use? Beating the blank page without losing your voice
• 1:19:06 Wrap-up: coaching availability, training from 50 to 53, and where to find Bryan

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Dr. Gregory Kelly, N.D., is Chief Product Officer at Qualia Life, a naturopathic physician, author of Shape Shift, and former editor of Alternative Medicine Review.

Detox is more than a liver story—and it is not a juice cleanse. Dr. Gregory Kelly of Qualia Life explains how clearance pathways work together, why mobilizing stored chemicals is not the same as eliminating them, and the thinking behind Qualia 2-Day Detox.

Expect to learn why detox skepticism is warranted, how Dr. Kelly thinks about cumulative stress and chemical exposure, what liver biotransformation and elimination mean, why his formulation includes a between-meals binder stack, how sleep and the glymphatic system enter the conversation, and what Qualia’s small symptom-questionnaire study can and cannot establish—and much more.

Dr. Kelly discusses his company’s Qualia 2-Day Detox product. Product descriptions and health claims are his views, not independent verification or medical advice; the small study discussed used self-reported symptom questionnaires.

Connect with Greg:

• Qualia on Facebook
• Qualia on Instagram
• Qualia on TikTok
• Dr. Gregory Kelly on LinkedIn

Episodes you'll enjoy next:

• Episode 352: Dr. Dan Pardi on Stem Cells, Supplements, and the Future of Health with Qualia: Dr. Dan Pardi on stem cells, supplements, cognitive performance and health habits at Qualia.
• Episode 310: Unpacking the Science of Sleep with Dr. Allison Brager: Neuroscientist Dr. Allison Brager on sleep phases, circadian rhythms and performance.

Episode Timestamps:

• 05:03 Detox skepticism and why this conversation matters
• 06:35 Why Qualia chose to develop a detox product, according to Dr. Kelly
• 08:08 Who might need detox support, and Mike's experience with wildfire air pollution
• 09:42 Dr. Kelly's environmental medicine background and the "last straw" bucket analogy for stress load
• 12:44 Exposures Dr. Kelly tries to limit: canned foods, strong scents, new furniture, indoor air
• 15:59 Small, consistent changes versus one silver bullet; Dr. Kelly cites biomonitoring studies
• 18:59 Water filtration and drinking-water habits
• 21:32 Larger exposures, the precautionary principle, mold, and skin products
• 24:18 Sunscreen, sun exposure, and not overcomplicating health choices
• 28:39 How Qualia approached the formulation, and an explanation of phase one, two, and three liver pathways
• 33:07 Dr. Kelly's description of the four-step packets: morning and with-meal
• 36:28 The between-meals binder stack, and a weight-loss study Dr. Kelly cites on stored chemicals
• 40:26 The bedtime packet, the glymphatic system, and brain demands when learning new skills
• 44:35 Fat-loss phases, a two-days-a-month approach, and Qualia's small symptom-questionnaire study
• 48:49 Dr. Kelly's pairings for detox days: sauna, gentle movement, hydration, skin brushing, baths
• 54:24 Wrap-up: fitting the routine into your schedule, and where to find more information

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In this episode of the Flex Diet Podcast, I break down why I built the Physiologic Flexibility Certification (PhysFlex) as a “level two” continuation after you’ve already got the basics of nutrition, training, and recovery mostly dialed in. I explain how Phys Flex targets four overlapping homeostatic regulators—temperature (heat/cold exposure), pH (acidity/alkalinity shifts), expanded fuels (ketones and lactate), and oxygen/CO2 regulation (breathing)—and why taking a systems view matters more than treating everything in silos.

I share examples of how these pillars can become the real limiter in recovery and performance, including high-intensity work, long-duration events, and signs like elevated overnight respiration rate. Enrollment is open from Monday, October 12 through midnight PST Monday, October 19, 2026, and I’m offering direct email access for questions.

Enroll here: https://physiologic.miketnelson.com/sales

Episode Timestamps:

• 00:00 Welcome and Podcast Focus
• 00:19 Course Enrollment Window
• 01:44 Who This Certification Is For
• 02:48 Why Four Pillars Together
• 03:41 The Four Homeostatic Pillars
• 05:05 Systems Thinking Over Silos
• 08:07 Applying the Framework to Recovery
• 11:41 Course Structure and Interventions
• 13:09 Support, Email Access, Next Guest
• 13:58 Medical Disclaimer and Closing

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Dr. Jordan Shallow, D.C., known as “The Muscle Doc,” is a chiropractor, strength and conditioning coach, and former competitive powerlifter. He is the founder of Pre-Script®, an education company that teaches coaches applied biomechanics and resistance training.

Is getting stronger really about muscle, or about how well your nervous system learns the lift? Dr. Jordan Shallow, “The Muscle Doc,” explains why strength and size follow skill, how your senses shape movement, and how simple sensory inputs may change the way you train.

Expect to learn when internal versus external cues make sense for strength and hypertrophy, how an intermediate lifter can use practice volume and frequency, why great lifters treat the empty bar like the heavy one, how touch, vibration, skin stretch and pressure may influence movement, and how neuroplasticity, lucid dreaming and film study connect to learning skills — and much more.

Connect with Jordan:

• Website: themuscledoc.com
• Pre-Script: pre-script.com
• Instagram: @the_muscle_doc
• Pre-Script on Instagram: @pre_script

Episodes you'll enjoy next:

• #401 — Psychedelics, Neuroplasticity and the Military-to-Spiritual Journey with Rick Alexander: A former Special Operations combat medic explains how a psychedelic experience reshaped his worldview, and what it taught him about neuroplasticity.
• #311 — Maximizing Athletic Performance with Neurology: Insights from Dr. Dylan Seeley: Dr. Dylan Seeley on how applying neurology can improve athletic performance.

Episode Timestamps:

• 03:47 Internal vs. external cues for strength and hypertrophy
• 06:24 Longevity culture and why skill comes before loading
• 09:58 Intermediate bench press case study: practice volume and frequency
• 17:34 Ed Coan, intent and moving the empty bar like the heavy bar
• 23:30 Sensory-motor savants: Tiger Woods, Nick Kyrgios and Brian Shaw
• 27:29 How trainable is the sensory system?
• 29:35 Foam rollers, kinesio tape and cupping through a neurological lens
• 32:10 Perception, the electromagnetic spectrum and the limits of our senses
• 36:23 Mechanoreceptors and vibration
• 41:05 Light touch, vibration, skin stretch and deep pressure
• 47:14 Fast feedback: testing and iterating with the nervous system
• 51:38 Neuroplasticity, psychedelics and learning skills faster
• 1:02:45 Reality Switch Technology, tropanes and perception
• 1:05:08 Dreams, hypnagogic hallucinations and altered perception
• 1:12:26 Lucid dreaming and practicing the deadlift without the load
• 1:23:19 Film study, muscle memory and watching good reps
• 1:26:37 Where to find Dr. Jordan Shallow

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Dr. Martin Gibala is a Professor of Kinesiology at McMaster University and one of the world's leading researchers on high-intensity interval training.

Can short bursts of hard cardio outperform hours of Zone 2 for the average person? Exercise physiologist Dr. Martin Gibala explains how HIIT can improve VO2 max and metabolic flexibility, why elite athletes' 80/20 split may not fit a time-strapped schedule, and how to judge vigorous effort without chasing a perfect heart-rate zone.

Expect to learn how to scale HIIT for beginners, what RPE and the talk test reveal about vigorous effort, when short sprints differ from VO2 max intervals, why elite athletes’ 80/20 approach may not fit your schedule, how Zone 2 definitions can mislead, and what metabolic flexibility and mitochondrial capacity really mean—and much more.

Connect with Martin:

• Website: martingibala.com
• X: @gibalam
• Book: The One-Minute Workout (Avery, 2017; with Christopher Shulgan)
• Podcast: Exercise Science

Episodes you'll enjoy next:

• #402 — VO2 Max, Zone 2 Training & the Psychology of Human Performance — Ben Skutnik: Dr. Ben Skutnik cuts through Zone 2 hype and discusses VO2 max and aerobic-training evidence.
• #387 — Nathan T. Jenkins on Metabolic Flexibility, Aerobic Base, and First Principles: a look at aerobic development, energy systems, and repeated high-intensity performance.

Episode Timestamps:

• 2:25 Can beginners benefit from HIIT?
• 4:20 Interval training basics and scaling effort
• 7:13 Defining vigorous effort with RPE, heart rate, and the talk test
• 11:32 Designing HIIT workouts around time and preference
• 13:48 VO2 max intervals versus shorter sprints
• 16:39 Moderate versus vigorous exercise: guidelines and time efficiency
• 18:36 Is Zone 2 and the 80/20 rule right for everyone?
• 22:50 Why Zone 2 definitions and wearables cause confusion
• 29:12 Do you need an aerobic base before starting intervals?
• 33:00 Why elite athlete training is not a blueprint for everyone
• 35:22 What low-intensity volume may do for endurance athletes
• 38:46 Double-threshold sessions, training stress, and recovery
• 41:17 Carbohydrate intake and gut training in endurance sports
• 44:31 Emerging recovery strategies and exogenous ketones
• 49:12 Lactate supplementation: promise versus current evidence
• 51:19 Fat max, metabolic flexibility, and mitochondrial capacity
• 55:31 Exercise Science podcast and evidence over hype

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Matthew Paul Clemons, MD, is a diagnostic radiologist specializing in nuclear medicine and body imaging. He is Head of Nuclear Medicine at Radiology Partners Houston and a rectal and prostate cancer specialist.

Whole-body MRI promises a detailed look under the hood—but what can a quick screening scan actually see, miss, and send you chasing? Dr. Paul Clemons explains why a whole-body MRI is a limited study, how incidental findings can lead to further tests, and why standard screening remains the better choice for most people.

Expect to learn how MRI creates images and why scan protocols take time, why open MRI systems can have important image-quality limits, how PET/MRI adds functional information, why CT and MRI can be complementary rather than redundant, how radiation and implanted devices factor into decisions, why spine findings do not always match symptoms, when conservative care deserves consideration, and where DEXA versus MRI can be useful for tracking body-composition trends.

Episodes you'll enjoy next:

• #237 — Demystifying Body Composition Testing with Dr Grant Tinsley and Dr Eric Helms: a practical companion discussion on body-composition measurement and its limits.
• #159 — Advice, Mentorships, Askholes, and Diagnostics: An Interview with Dr. Adam Sumarski: a related conversation on diagnostics and imaging in sports medicine.

Episode Timestamps:
1:50 Whole-body MRI and preventive screening
2:52 How MRI works: magnets, noise, and safety
7:05 Open MRI, magnet strength, and image quality
9:05 MRI sequences, scan time, and diagnostic protocols
11:47 Why whole-body MRI is a limited screen
12:46 Incidental findings and downstream testing
13:57 High-risk screening, rare genetic conditions, and lung limits
17:53 Sensitivity, specificity, and standard screening
24:15 PET/MRI and where whole-body imaging has a clinical role
27:05 Why MRI and PET/CT systems are expensive to install
31:59 MRI safety, implants, and pacemakers
36:36 CT versus MRI: why one scan can lead to another
38:52 Whole-body CT, radiation, and its limits
43:47 Back-pain scans: why an image may not explain symptoms
51:44 Physical therapy, surgery, and warning signs
58:46 Evaluating evidence for peptides, stem cells, and biologics
1:05:47 Choosing an orthopedic surgeon for athletic goals
1:15:24 DEXA versus MRI for body-composition trends

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Dean Guedo is an Edmonton, Alberta-based online nutrition coach and strength/nutrition professional with roughly a decade in fitness, athletics and strength sports, and Jeb Stuart Johnston is a National Board Certified Health & Wellness Coach and the Charleston, SC-based founder of Food on the Mind, specializing in emotional eating and food obsession.

Dean and Jeb join Dr. Mike T Nelson for their yearly AI check-in, getting into whether creators should disclose AI use and why deepfaked video is a very different beast than AI-assisted writing. The conversation ranges into dead internet theory, why so much hard-won fitness expertise never made it onto the internet at all, and why demanding physical skills may become more valuable, not less, as AI accelerates.

Expect to learn whether creators should disclose their AI use and why deepfaked video is a fundamentally different risk category than AI-assisted writing, why LLM writing may have already "peaked" and regresses toward the average, why fitness's hard-won oral tradition (Charlie Francis, Louie Simmons, old forums) never made it onto the internet at all, why oral defense of your own thinking may be the most AI-proof skill you can build, and why demanding physical skills could become more valuable — not less — as AI accelerates, and much more.

Connect with Dean:

• Instagram: @walk.more.king
• Website: https://getfluxed.ca

Connect with Jeb:

• Website: https://www.foodonthemind.com/
• Instagram: @jebstuartjohnston
• Newsletter: Tangential, Inconsequential, Existential and Experiential (Substack)

Episodes you'll enjoy next:

• Episode 136 — Flex Diet, Phys Flex, Metabolism and Nutrition Research for Compound Performance (Jeb and Dean interview Dr. Mike T Nelson): Listen here
• S2 Ep 28 — High Flux Model and More for Fat Loss and Client Coaching, an interview with Dean Guedo and Jeb Johnston of StrongerU: Listen here

Episode Timestamps:

• 01:35 Welcome to the podcast & guest introductions
• 03:15 Should you disclose your AI use?
• 06:32 Deepfake video vs. AI-assisted writing: a different risk category
• 07:53 AI's exponential growth and the "singularity" question
• 11:11 What is "AI slop," and does it actually matter?
• 12:42 Why LLMs regress toward average (and the Reddit problem)
• 15:15 Falsely accused of "AI slop" for your own writing style
• 21:36 "Automate your business with AI" — the wrong things to automate
• 25:23 Dead internet theory: has AI writing already peaked?
• 26:34 Why AI can't reason about truly novel, hypothetical situations
• 28:37 Hemingway's unfinished-thought trick and "open-loop" thinking with AI
• 35:06 Why weird, opinionated writing might be AI-proof
• 44:49 Fitness's lost oral tradition: Charlie Francis, Louie Simmons, old forums
• 47:03 Stoner, the trivium, and teaching without teaching
• 48:06 Oral defense as the AI-proof assessment
• 56:08 Research vs. coaching: the application gap (Norwegian 4x4, tabata)
• 1:07:26 Will AI push us back toward hard physical skills?
• 1:15:00 Where to find Jeb & Dean

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Don Saladino is a New York-based coach and health entrepreneur who has trained A-list clients like Ryan Reynolds, Hugh Jackman, and Blake Lively since founding Drive495 in 2005.

Don Saladino has spent nearly three decades training A-list stars like Ryan Reynolds and Hugh Jackman — and in this episode, he shares the single business lesson he wishes he’d learned sooner. He and Dr. Mike also dig into why Don closed his $2M-overhead NYC gym, how tracking respiratory rate reshaped his approach to Zone 2 training, and the sobering personal loss that changed how he views performance enhancers.

Expect to learn why Don stopped over-certifying and started looking at what’s leaking in his business, how he built 17 years of trust with a client like Ryan Reynolds, the real financial toll of running a NYC gym (think $1M rent and $2M overhead), what tracking respiratory rate taught him about Zone 2 training volume, his honest take on performance enhancers at 49 (natural), and the personal loss that reshaped how he views unsupervised PED use, and much more.

Connect with Don:

• Website
• Instagram
• YouTube

Episodes you'll enjoy next:

• #402 — VO2 Max, Zone 2 Training & the Psychology of Human Performance — Ben Skutnik: Listen here
• #397 — How Elite Bodybuilders Think About Problem-Solving, Business and Nutrition with Coach Cliff Wilson: Listen here

Episode Timestamps:

• 2:26 — #1 Business Lesson: Stop Over-Certifying, Start Looking at What’s Leaking
• 5:43 — “Content Is King, Distribution Is the Kingdom”
• 8:35 — Take Risks Early: Betting on Yourself Before Responsibilities Pile Up
• 10:58 — Learning Business Over Breakfast: The NYC Advantage
• 12:01 — The Art of Adding Value Without an Agenda
• 13:32 — Working With Ryan Reynolds for 17 Years: Trust, Humility & Knowing You’re Replaceable
• 21:12 — What It Really Takes to Work With High-Profile Clients
• 26:26 — Actors vs. Athletes: Which Is Harder to Train?
• 28:39 — Performance Enhancers: Don’s Honest Take at 49, Natural
• 36:31 — Tracking Respiratory Rate & Rethinking Zone 2 Volume
• 38:37 — Closing the NYC Gym & Pivoting to Digital
• 43:35 — The Real Cost of Running a NYC Gym: $1M Rent, $2M Overhead
• 44:32 — Business Lessons You Can’t Learn at Harvard
• 46:09 — The “Integrated Wellness” Facility Trend: Is Anyone Actually Getting It Right?
• 1:05:26 — The Rise of Recovery Studios: New Happy Hour or Legit Wellness?
• 1:08:44 — A Personal Loss & a Stark Warning on Unsupervised PED Use
• 1:16:27 — Where to Find Don Saladino

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Dr. Ben Skutnik, PhD, CSCS*D, NSCA-CPT*D, is an Assistant Professor of Kinesiology and Human Performance Lab Director at Butler University and Head of Nutrition Coaching at Power Athlete.

Dr. Ben Skutnik joins the show to separate fact from fad in aerobic training, debunking zone 2 hype and explaining why VO2 max matters but isn't everything.

Expect to learn why reading scientific literature is its own skill, how uncontrolled variables quietly derail hypertrophy and menstrual-cycle training research, why treating people as fragile backfires, why anecdote in human performance often outruns the research, how "closing the loop" with clients beats chasing mechanisms, what the Norwegian 4x4 method gets right (and what most zone 2 research gets wrong about training zones), and how to actually build VO2 max with the critical power model, and much more.

Connect with Ben:

• Power Athlete Coach Bio
• LinkedIn
• Google Scholar

Episodes you'll enjoy next:

• #400 — Build Aerobic Fitness Before Mitochondrial Peptides: AMPK, VO2 Max & Recovery — Dr. Dwayne Jackson: Listen here
• #374 — Zone 2 Cardio: What the Science Really Says (Pros, Cons & Better Options) with Kristi Storoschuk: Listen here

Episode Timestamps:

• 1:46 — Why Ben was recommended for this conversation on cardiovascular and aerobic programming
• 7:31 — Reading scientific literature is a skill set of its own
• 14:05 — Hypertrophy training to failure and uncontrolled variables in research
• 16:27 — Debunking myths about training around the menstrual cycle
• 18:20 — Human resilience and the danger of treating people as fragile
• 22:09 — Why consistency beats trying to "hack" optimization
• 22:40 — Nutrition fear-mongering and overly restrictive diets
• 27:25 — Changing one variable at a time vs. the "kitchen sink" approach
• 29:55 — Why anecdotal evidence in human performance is often ahead of the research
• 34:48 — The ethics of placebo and "closing the loop" with clients
• 37:34 — The psychology of performance: the NFL kicker example
• 43:13 — The Norwegian 4x4 method and zone 2 training myths
• 46:40 — Why most zone 2 research relies on the wrong zone model
• 52:53 — HYROX, CrossFit, and Goodhart's Law in training
• 1:05:18 — Is VO2 max overrated? Performance vs. health tradeoffs
• 1:15:25 — Building VO2 max: interval protocols and the critical power model
• 1:26:02 — Life-changing results: taking deconditioned clients from VO2 max 18 to 35
• 1:30:09 — Where to find Ben Skutnik and his work at Butler University and Power Athlete

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Rick Alexander is a depth-psychological counselor, psychedelic practitioner, and interfaith spiritual care provider currently completing his Ph.D. in Mythology/Depth Psychology and a former Naval Special Operations combat medic.

Rick was a Special Operations combat medic until a single psychedelic experience shattered his worldview and sent him back to school to study psychedelic spiritual care. He and Dr. Mike dig into neuroplasticity windows, why “good trip/bad trip” is the wrong question, and what may really be happening in DMT space.

Expect to learn how a rough teenage salvia trip and a later psilocybin experience redirected Rick's entire career, what life is really like as a Special Operations Combat Medic supporting SEALs and Green Berets, why military training narrows emotional range and makes civilian re-entry so hard, how integration (not the trip itself) determines whether a psychedelic experience heals or destabilizes you, what the "third wave" of psychedelic science gets right that the DSM's "hallucinogen" label gets wrong, whether neuroplastic windows could help athletes learn skills faster, and what a brutal 5-MeO-DMT experience taught Rick about his own running form and breathing.

Connect with Rick:

• Website
• Instagram

Episodes you'll enjoy next:

• #47 — Tools to Down-Regulate in Response to Stress (an earlier conversation with Rick Alexander): Listen here
• #194 — The Pros and Cons of Psychedelic Compounds with Psychedelic Researcher Rebekah Senanayake: Listen here

Episode Timestamps:

• 2:49 – Rick's PhD progress and the psychedelic experience that redirected his career
• 3:38 – A rough first psychedelic experience with salvia at 18
• 4:46 – The psilocybin experience that "peeled back" his worldview
• 7:00 – Life as a Special Operations Combat Medic supporting SEALs and Green Berets
• 8:23 – How military training narrows emotional range and worldview
• 10:01 – Why veterans struggle to re-enter civilian life after specialized training
• 13:34 – The double-edged sword: psychedelics can destabilize as easily as they heal
• 14:32 – The "third wave" of psychedelic science and the flawed DSM "hallucinogen" label
• 23:49 – Integration: do you have time to process what comes up?
• 24:43 – "Psychedelic myth-making" and building a new personal mythology
• 31:05 – Could neuroplastic windows help athletes learn skills faster?
• 37:01 – Yogic energy channels (nadis) and psychedelics amplifying subtle perception
• 39:17 – How a brutal 5-MeO-DMT trip changed Rick's running form and breathing
• 56:16 – What's really happening in DMT space: Strassman, Gallimore, and "reality switch technologies"
• 59:43 – Henri Corbin's "psycho-cosmology": consciousness and reality as mirrored levels
• 1:06:45 – "Functional consequentialism": why you shouldn't dismiss someone else's experience
• 1:10:46 – Where to find Rick and his counseling and breathwork work

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Dr. Dwayne Jackson is a health specialist, medical educator, scientist, and entrepreneur with a PhD in neurovascular physiology.

Mitochondrial peptides may be promising, but they cannot replace the aerobic base that makes their effects measurable. Dr. Dwayne Jackson explains AMPK and mitochondrial signaling, what MOTS-c and SS-31 can and cannot tell us, and why fitness data, training, and recovery come before any experimental compound.

Expect to learn how aerobic fitness supports strength and Strongman training, why lactate clearance and conditioning can become the rate limiter, what AMPK and mTOR signal, how kidney disease changed Dwayne’s perspective on aerobic capacity, where the evidence for MOTS-c and SS-31 is limited, how to design a more useful N-of-1 experiment, and why training, nutrition, recovery, COAs, and third-party testing come before experimental compounds.

Connect with Dwayne:

• Website: drdwaynejackson.com
• Google Scholar

Episodes you’ll enjoy next:

• #396 — Are Your Peptides Illegal? — Rick Collins: A practical look at peptide science, regulation, and the gray market.
• #393 — From Powerlifter to Trail Runner — Paul Oneid & Cody Miller: VO2 max, cardiac adaptations, and the transition from strength sports to endurance.

Episode Timestamps:

• 01:53 — Mitochondrial peptides and the aerobic-training foundation
• 03:19 — Peptides as training amplifiers, not replacements
• 04:22 — AMPK, mTOR and mitochondrial signaling
• 05:50 — Why aerobic fitness supports strength and Strongman training
• 08:12 — Conditioning, lactate clearance and the rate limiter for strength athletes
• 10:58 — Wingate tests and overlapping energy systems
• 15:12 — Kidney disease, mitochondrial dysfunction and aerobic collapse
• 21:22 — Hypertensive crisis, dialysis and recognizing a major fitness decline
• 24:48 — Kidney transplant recovery and rebuilding aerobic capacity
• 28:27 — The evidence and limitations behind mitochondrial peptides
• 34:55 — MOTS-c, AMPK activation and anecdotal HIIT performance
• 39:59 — SS-31, cardiolipin and mitochondrial efficiency
• 48:32 — Why training, nutrition and recovery come before peptides
• 58:40 — Using performance data to make an N-of-1 experiment more useful
• 1:01:22 — SS-31 before training, AMPK timing and recovery trade-offs
• 1:06:07 — SLU-PP-332, exercise mimetics and the gap in human data
• 1:09:17 — Peptide sourcing, COAs and third-party testing
• 1:12:02 — Genetics, response variability and sustainable performance

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

Emily Werner, PhD, RD, CSSD, IFNCP is Team Dietitian for the Philadelphia 76ers (NBA) and Philadelphia Flyers (NHL), and Nutrition Affairs Sport Lead at Timeline.

Dr. Emily joins Dr. Mike to unpack postbiotics, urolithin A, and why mitochondrial health matters for pro athletes and everyday people alike, digging into the real research behind Timeline's Mitopure and why chasing $200K gadgets rarely beats getting the fundamentals right.

Expect to learn what a postbiotic actually is and how urolithin A differs from other supplements, why old-school and new-school sports dietitians disagree on peptides and supplement fads, how chronic undereating quietly undermines performance in women's sports, what the current human performance research on urolithin A actually shows, how Mitopure is dosed and why urolithin A can't be reliably food-sourced, and why product quality and manufacturing integrity matter more than marketing claims, and much more.

Connect with Emily:

• Website: https://www.eateliteperform.com/
• Instagram: @emilywerner34
• LinkedIn: https://www.linkedin.com/in/emily-n-werner-phd-rd-cssd-ifncp-4a820a97/

Episodes you'll enjoy next:

• #377 — Methylene Blue for Mitochondria & Performance: Benefits, Dosing & Risks with Dr. Scott Sherr: Listen here
• #382 — Creatine for Muscle, Bone, Brain & Longevity (Plus Caffeine, Dosing, and Safety) with Dr. Darren Candow: Listen here

Episode Timestamps:

2:21 Welcome & introductions
6:09 What is a postbiotic? Pre-, pro-, and postbiotics explained
7:09 Urolithin A: the postbiotic behind Mitopure
8:19 How Emily started consulting for Timeline
10:11 Old-school vs. new-school sports dietitians on supplements
13:53 Peptides, anecdata, and why athletes ignore the data
20:05 The hardest lesson: letting go when clients won't listen
21:15 Money, ego, and athletes chasing $200K wellness gadgets
24:53 Chronic undereating in women's sports
30:48 Nutrition's real job: keeping athletes available to play
33:19 Inside Mitopure: Timeline's flagship urolithin A product
35:06 Mitochondria, mitophagy, and why they matter as we age
38:16 Diet, fasting, and exercise as natural mitophagy triggers
43:36 What the performance research on urolithin A actually shows
53:19 Aging, aerobic capacity, and Emily's 101-year-old grandma
55:40 Mitopure dosing: how much urolithin A and when to take it
57:14 Why urolithin A can't be food-sourced (and can't be faked)
1:03:19 Why product quality and integrity matter in supplements

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

Zach Moore is a nutrition and exercise coach based in southern Indiana, coaching clients online and in person.

Zach cuts through the noise of complicated programming and diet protocols to get back to what actually works — minimalist strength training, honest macro-setting, and paying attention to gut health and micronutrient status before chasing anything fancier.

Expect to learn how to build serious strength with far less training volume than you think, why chasing perfect programming conditions is often a waste of energy, how Zach sets carbohydrate and macro targets for real-world clients, when (and when not) to bother with micronutrient or gut testing, and why micronutrients matter even on restrictive or elimination diets, and much more.

Connect with Zach:
Website: https://zmoore.com
Instagram: @ZachMFitness

Episodes you'll enjoy next:

• #388 — What Vinegar & Lifting Really Do To Your Gut: Listen here
• #397 — Why Getting Better Never Gets Easier with Cliff Wilson: Listen here

Episode Timestamps:

• 02:37 Training in a garage gym during a heat wave
• 03:53 Grip strength, sweat & cold water immersion
• 06:32 Overthinking training & lessons from old-time strongmen
• 09:54 Minimalist strength training & the trap bar deadlift
• 15:13 Go-to lifts & why you must add muscle for body comp
• 17:42 Progressive overload & long-term strength gains
• 19:56 How too much program variety kills progress
• 27:06 Individualizing & dialing in training volume
• 30:42 Favorite upper & lower body exercises
• 35:46 Nutrition foundations: informed eating
• 38:10 Eating enough to fuel training & recomp
• 44:06 Determining carb needs & setting client macros
• 48:13 The insulin myth: do carbs turn into fat?
• 52:40 Meal balance, fat timing & digestion
• 55:34 Tracking micronutrients with Cronometer
• 58:13 Gut testing, carnivore & elimination diets
• 1:02:25 Sleep tips: circadian rhythm, light & temperature
• 1:04:39 The Shiftwave chair for stress downregulation & sleep

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

Cliff Wilson is a physique coach with over 16 years of experience working with bodybuilders and physique athletes of every level, including 24 world champions and the current natural bodybuilding world champion.

Getting better doesn’t make hard things feel easier—it makes you capable of doing more. Cliff Wilson explains the mental skills behind elite physiques, why context beats internet absolutes, and how great coaches turn research, experience, and failure into better decisions.

Expect to learn why impulse control makes up 20–50% of physique coaching, why you have to learn to dribble before you try to dunk, why practitioners and social media commentators are not the same thing, why getting fitter never makes a true max effort feel easier, how context (not absolutes) explains wildly different carb intakes between world-class physique athletes, why most advanced bodybuilders eventually land back on a bro split, and what separates “collectors” of credentials from coaches who can actually integrate and apply what they know—and much more.

Connect with Cliff:
https://teamwilsonbb.com (book: Becoming Unrivaled)
Instagram: @cwteamwilson
Raw Intensity app (mentioned in the episode)

Episodes you'll enjoy next:
#323 — Natural vs. Enhanced Bodybuilding: An In-Depth Chat with Aaron Straker: https://flex-diet-podcast.simplecast.com/episodes/episode-323-natural-vs-enhanced-bodybuilding-an-in-depth-chat-with-aaron-straker
#167 — The Physiologic and Psychologic Benefit of Doing Hard Things: Akshay Nanavati of Fearvana: https://flex-diet-podcast.simplecast.com/episodes/episode-167-the-physiologic-and-psychologic-benefit-of-doing-hard-things-akshay-nanavati-of-fearvana-with-dr-mike-t-nelson

Episode Timestamps:

• 02:15 — The edited interview begins and Mike explains the unusual opening
• 02:49 — Why 20–50% of physique coaching is impulse control
• 05:19 — Skill levels: learn to dribble before trying to dunk
• 07:37 — Practitioners vs. social media commentators
• 10:45 — Why you cannot sidestep the hard parts of fat loss
• 12:44 — Getting fitter does not make a true max effort feel easier
• 14:04 — Context beats absolutes: 700 grams vs. 50 grams of carbs
• 19:26 — Slow thinking, pondering, and turning information into insight
• 21:57 — Giving clients autonomy dramatically improved results
• 25:18 — Range, cross-domain learning, and better problem-solving
• 27:03 — Using OODA loops to make better coaching decisions
• 28:24 — Why most advanced bodybuilders return to a bro split
• 31:42 — Low-volume training, outliers, and small-sample traps
• 44:01 — A surprising DNA result and the role of elite genetics
• 48:31 — Michael Phelps, elite rituals, and competitive mindset
• 50:43 — Why bodybuilding coaching skill may have declined
• 53:11 — Objectivity, Austin Stout, and the traits of great coaches
• 01:03:14 — Collectors vs. integrators: credentials are not application
• 01:08:07 — Cliff's Raw Intensity app and upcoming book Becoming Unrivaled

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

Rick Collins, Esq., NSCA-CSCS, is a lawyer who defends the nutrition and fitness community, a partner at Collins Gann McCloskey & Barry PLLC, and General Counsel to the International Society of Sports Nutrition.

Peptides are everywhere right now, but most of what's sold online as BPC-157 or TB-500 is illegal — and the FDA is about to decide what happens next. Rick breaks down the science, the legal gray market, and why the military's new testosterone screening policy matters too.

Expect to learn what actually counts as a "peptide," how GLP-1 drugs normalized injectable medications and fueled the gray market, what the FDA's own scientists concluded about BPC-157 and TB-500, why Rick's caseload has shifted from steroids to 80-90% peptide cases, what a possible "experimental peptide" middle-ground category could look like, and what really happens when the FDA raids a peptide seller, and much more.

Connect with Rick:
http://www.RickCollins.com

Episodes you'll enjoy next:
#371 — Peptides, TRT, GLPs & Bloodwork: How to Do It Safely (and What Most People Miss) with John Gorman: Listen here
#319 — Exploring the World of Peptides with Anthony Castore: Listen here

Episode Timestamps:
4:07 Rick's background as a lawyer and his standard legal disclaimer
6:14 What actually counts as a "peptide"
8:25 How GLP-1 drugs normalized injectable medications
10:44 Loss of trust in the FDA fuels the gray market
11:46 The rise of personal health autonomy
13:40 Two markets: the medical model vs. "bro science"
16:23 Inside the FDA Compounding Advisory Committee meeting
19:23 FDA scientists' verdict on BPC-157 and TB-500
20:49 Why the science on BPC-157 is still so thin
22:07 Prohibition logic: the black market will keep growing
25:47 A possible middle ground: an "experimental peptide" category
32:11 Rick's caseload shift — from steroids to 80-90% peptide cases
35:30 Why big pharma cares about tirzepatide and retatrutide knockoffs
42:28 Pete Hegseth and testosterone screening in the military
46:57 Why the new TRT policy may be "much ado about nothing"
49:23 Low testosterone's real, well-documented health risks
52:26 Richard Dawkins, The Selfish Gene, and biohacking against nature
57:12 The schism between orthodox medicine and biohacking
62:39 What happens when the FDA raids a peptide seller
63:30 Connect with Rick Collins

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

Samuel Brown, M.Ed., CSCS is a Cognitive Performance Specialist for the U.S. Air Force and a strength and conditioning professional who has worked everywhere from collegiate athletics to elite tactical units.

Sam spends his days training Air Force pilots and aircrew who run on nicotine, caffeine, and alcohol — and almost never turn off their nervous system. In this episode he reveals why the toughest operators need recovery just as much as intensity, and what years of coaching in Altus, Oklahoma taught him about real performance under extreme cognitive load.

Expect to learn what Air Force pilots are actually like to train, why the nicotine-caffeine-alcohol "trifecta" dominates military performance culture, how the physical act of flying itself takes a hidden toll through vibration and posture, why sympathetic nervous system domination cements poor posture and movement patterns, how Sam sneaks down-regulation into hard training sessions disguised as recovery work, and why resting heart rate might be a better performance metric than any wearable, and much more.

Connect with Sam:
https://www.instagram.com/sambrownstrength

Episodes you'll enjoy next:

• #312 — Optimizing Stress and Performance for Firefighters and Tactical Athletes with Dr. Drew Gonzalez: Listen here
• #310 — Unpacking the Science of Sleep with Dr. Allison Brager: Listen here

Episode Timestamps:

• 01:59 – What Air Force Pilots Are Actually Like
• 07:21 – Back to Basics: Training with Minimal Equipment
• 10:13 – Breaking the Instagram Training Cycle
• 12:06 – Endurance Trends Among Pilots
• 17:05 – The Air Force Trifecta: Nicotine, Caffeine & Alcohol
• 20:31 – Physical Toll of Flying: Vibration, Posture & Injury
• 23:44 – Stress Cements Posture: The Sympathetic Domination Problem
• 28:06 – Down-Regulation Protocols After Training
• 30:47 – Hiding the Pill in the Peanut Butter
• 47:44 – Wearables & the Loss of Body Awareness
• 50:31 – Resting Heart Rate as the Performance Metric
• 52:14 – The GOAT Drill for Cognitive Load & Recovery
• 1:02:31 – Building a Culture of Buy-In & Program Integration

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

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

Dr. Krista Scott-Dixon, PhD, is the author of the 700-page textbook Applied Nutrition Coaching and Counseling for Coaches.

Most nutrition coaches know their protocols — but very few have been trained in what to actually do when a client says something unexpected, breaks down, or simply won't follow the plan. Dr. Krista Scott-Dixon reveals the counseling techniques that most nutrition coaches have never learned — and why mastering them matters more than any protocol. She explains why over-optimized clients are often the most fragile, how AI is eroding the critical thinking skills coaches rely on, and what it really takes to translate complex science into simple, effective actions.

Expect to learn why LLMs are story-making machines that confidently get facts wrong, how the broken healthcare system is pushing patients toward fringe advice, what body awareness coaching actually looks like in practice, why Dunning-Kruger applies to both coaches and clients, how to help clients prepare better conversations with their doctors, and what makes coaching an irreplaceable human profession — and much more.

Connect with Krista:
Website: https://kristascottdixon.com/
Instagram:https://www.instagram.com/stumptuous
Facebook - https://www.facebook.com/coach.krista.scottdixon
1% Better Academy - https://onepercentbetteracademy.com/

Episodes you'll enjoy next:
#328 — Grit Gains: Building Mental Toughness and Resilience in Training with Ben Mayfield Smith: https://miketnelson.com/podcast/episode-328-grit-training-and-resilience-ben-mayfield-smith
#373 — The Future of Fitness + Healthcare: Coaches, Blood Work, and Client-Centered Models: https://flex-diet-podcast.simplecast.com/episodes/episode-373-the-future-of-fitness-healthcare-coaches-blood-work-and-client-centered-models-kevin-dineen-k12eNARO

Episode Timestamps:
02:02 The Dangers of AI for Health Research
03:40 LLMs as Story-Making Machines
04:35 Mike's AI Citation Fail & the 'Dead Internet' Theory
08:55 The Antidote: Getting Back to Basic Skills
09:55 Literacy, Critical Thinking & Health Literacy Crisis
16:55 The Broken Healthcare System & Why Patients Distrust Providers
18:20 Why Parents Seek Fringe Medical Advice for Their Kids
20:55 The Power of Simple Coaching Interventions
22:55 Coaching as Translation: Complex Science, Simple Actions
26:35 Teaching Clients Body Awareness & Self-Observation
28:55 Gym Culture & The Dissociative Society
30:55 When Clients Don't Know Why They Feel Bad
33:25 Helping Clients Prepare Better Conversations with Their Doctors
37:55 AI, Cortisol Grift & Bastardized Physiology
40:55 If It's So Easy, Show Me — Krista's Coaching Insight
45:55 Dunning-Kruger, Expertise & Learning to Question Everything
51:55 Decision-Making: Low Bullshit, Cool People, Meta Skills
56:55 Choosing Projects & Finding Your Authentic Fit
61:55 The Book: Who It's For & What It Covers
74:55 Coaching as a Human Profession (Not to Be Automated)
84:55 Sprinting, Scope of Practice & Knowing Your Clients
86:55 Where to Find Krista & Closing Thoughts

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

In this episode of the Flex Diet Podcast, I sit down with Paul Oneid, MS, MS, CSCS and Cody Miller for a conversation about rebuilding from injury and the transition from strength sports to endurance training.

Paul Oneid tore both quads and rebuilt himself from powerlifter to trail runner, with coach Cody Miller guiding the transition. They break down the emergent training approach, VO2 max and cardiac adaptations, and the mental side of suffering across strength sports and endurance.

In this episode, you'll learn:

• How Paul's decision to move away from powerlifting and bodybuilding after tearing both quads
• The emergent, responsive approach Cody used to build Paul's running base from scratch
• Why cardiac structural adaptations (like resting heart rate drops) take months, not weeks
• Cody's time-to-exhaustion model for structuring endurance intervals without needing lactate testing

Find Paul here:

https://masterathletic.com

https://coachescorneru.com

https://www.instagram.com/pauloneid/

Find Cody here:

https://hoopiestrength.com/

https://www.instagram.com/coach.cody.miller

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