How do muscles actually grow — and what really matters for hypertrophy?

In this episode, I break down muscle growth from the ground up, starting with muscle structure and working all the way through the practical training variables that actually drive hypertrophy.

We cover how muscle fibers are built, why muscle cells are uniquely multi-nucleated, and how satellite cells and myonuclei influence growth potential and long-term adaptations (including the concept of “muscle memory”). From there, we dig into how resistance training shifts net protein balance, why muscle protein synthesis and breakdown both rise with training, and why hypertrophy is often delayed when people first start lifting.

A major focus of this episode is mechanotransduction — how mechanical loading from resistance training is converted into chemical signals that stimulate muscle growth. We unpack what we know (and don’t know) about mTOR signaling, phosphatidic acid, kinase pathways, and why mechanical tension is the primary driver of hypertrophy.

From there, the episode gets highly practical. We break down:

• Why proximity to failure matters more than load

• How volume really works (and why “dose-dependent” doesn’t mean linear)

• The role of training frequency and how to distribute volume

• Why stretch and lengthened positions matter for growth

• Load and rep ranges for hypertrophy vs strength

• Exercise selection, machines vs free weights, and compound vs isolation lifts

• Rep tempo, intensity techniques, and what doesn’t meaningfully affect growth

• Why systemic hormone spikes from training don’t predict hypertrophy

I close with clear, evidence-based takeaways you can actually apply: how hard to train, how much volume most people need, when failure makes sense, how to structure exercises, and how to prioritize effort, recovery, and adherence over gimmicks.

If you want a science-based framework for building muscle — without myths, hype, or unnecessary complexity — this episode lays it out step by step.

SPONSORS

• Workout Builder – Customized training programs for all experience levels: https://biolayne.com/workout-builder

• Team Biolayne – One-On-One Coaching: https://biolayne.com/online-coaching

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

TIMESTAMPS

0:00:00 - Intro

0:04:53 - Muscle Function

0:06:23 - Muscle...

In this Building Muscle Masterclass, I sit down with Dr. Stu Phillips — the world’s most cited researcher in exercise science and protein metabolism. If you care about building muscle, eating enough protein, lifting smarter, or cutting through the noise in the fitness world, this is a must-listen.

Stu and I go deep on the biggest questions in hypertrophy and nutrition, backed by some of the most important studies in the field:

• What actually drives muscle growth and what most people still get wrong

• How much protein you should really eat to maximize hypertrophy (and what the meta-analyses say)

• Whether high-protein diets harm your kidneys (spoiler: nope)

• Plant vs. animal protein: does the source matter, or is it all about leucine?

• Do hormone spikes from training matter for gains?

• Should women change their programming based on menstrual cycle phase?

• The truth about “lifting heavy” — do you need it for hypertrophy?

And MORE

If you want the clearest, most up-to-date breakdown of protein science and muscle growth from the guy who literally did the research I base many of my recommendations on… this is your episode.

SPONSORS

• Carbon Diet Coach – 14 day free trial: https://joincarbon.com/podcast

• Workout Builder – Customized training programs for all experience levels: https://biolayne.com/workout-builder

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

FOLLOW STU

https://www.instagram.com/mackinprof

http://www.twitter.com/mackinprof

TIMESTAMPS

0:00:00 - Intro

0:01:50 - Background

0:08:33 - Biochemistry First

0:12:02 - Student Experience

0:14:53 - Single Most Important Thing for Muscle Growth

0:16:04 - Mechanisms of Hypertrophy

0:19:48 - Consistency is Key

0:21:46 - Muscle Growth and Hormones

0:28:34 - Acute vs Chronic

0:32:42 - Cortisol

0:36:19 - Carbon Diet Coach

0:37:19 - Muscle, Hormones, and Training for Women

0:49:56 - Training Auto-Regulation

0:55:42 - How Much Protein

1:08:06 - Workout Builder

1:09:02 - Protein and Kidneys

1:26:20 - Muscle and Metabolic Health

1:30:05 -...

In this week’s Q&A episode, I dig into your most common questions — from supplements to training to nutrition — and break them down with actual data, not influencer mythology. If you’ve ever wondered whether collagen is worth the hype, if fiber does more than “help you poop,” or whether turkesterone is anything more than TikTok creatine-with-a-fedora… this episode is for you.

We cover:

• Collagen:

Does it help joints? Skin? Connective tissue? Muscle? I walk through the clinical trials (including the ones influencers never mention) and explain where collagen actually works… and where it absolutely doesn’t.

• Fiber:

Yes, it helps your gut — but that’s just the start. We look at the research on mortality risk, insulin resistance, weight loss, inflammation, CKD, energy balance, colon cancer, and why higher fiber intake consistently predicts better health across multiple systems.

• Turkesterone & Ecdysteroids:

The internet loves calling this “natural anavar.” The human data… does not. I break down the preliminary studies, the animal research, and what’s real versus what’s marketing.

• Burnout & Training Balance:

How I manage training, work, and life without flaming out — and what actually matters for long-term consistency.

• Protein Needs After 40:

Do you need more protein as you age? What does the research say about anabolic resistance, amino acid signaling, and muscle protein synthesis in older lifters?

• Things That Hurt Muscle Growth:

Ice baths, alcohol, smoking, NSAIDs, corticosteroids — we go through the actual evidence on what blunts hypertrophy, what doesn’t, and what matters in the real world.

• Sugar & Weight Gain:

Do non-diabetics need to “fear” sugar? Or does it really come down to calories? We dig into metabolic ward studies, DIETFITS, high-sucrose diets, and the boring reality that calorie balance still wins.

• Men vs. Women in Training & Nutrition:

Sex differences in hypertrophy, strength gains, metabolic rate, and menstrual cycle effects on performance — what’s real and what’s bro-science?

• Training Over 50:

How many sets do you actually need to build muscle after 50? We review the dose-response data, multi-set vs single-set research, and the RCTs showing older adults can grow — there are no “non-responders.”

All research is cited directly from the studies mentioned — RCTs, meta-analyses, mechanistic papers, and long-term cohorts.

If you want evidence without the nonsense, this is your episode.

*SPONSORS*

• Workout Builder – Customized training programs for all experience levels: https://biolayne.com/workout-builder

• Physique Coaching Academy - Advanced Coaching and Nutrition Education for Personal Trainers: https://physiquecoachingacademy.com

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy:

Ultra-processed foods (UPFs) get a lot of negative press, but are they always as bad as people think? In this episode, I sit down with researcher Samuel Dicken, who recently led a high-profile randomized controlled trial on UPFs that challenged some long-held assumptions.

We dig into what his study found, why not all UPFs are created equal, and how the way we consume them might matter more than the processing label itself. At the same time, we explore why sticking with mostly minimally processed foods is still a sound piece of nutrition advice.

If you’ve ever wondered whether “ultra-processed” automatically means “unhealthy,” or how to make sense of the latest UPF research, you won’t want to miss this conversation.

SPONSORS

• David Protein - Buy 4 cartons, get 1 FREE at: https://davidprotein.com/pages/layne

• Carbon Diet Coach – 14 day free trial: https://joincarbon.com/podcast

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

FOLLOW SAM

https://www.instagram.com/drsamueldicken

http://www.twitter.com/SamuelDickenUK

TIMESTAMPS

0:00:00 - Intro

0:02:16 - Study Design

0:12:07 - Study Results

0:14:03 - NOVA Food Classification

0:18:53 - Research Misinterpretations

0:21:04 - Food Choices

0:24:34 - Zero Calorie Beverages

0:31:40 - Coke HFCS vs Cane Sugar

0:34:07 - David Protein

0:35:42 - Unintended Consequences

0:43:55 - LDL Cholesterol

0:47:50 - Ultra-Processed Foods Good or Bad?

0:53:11 - Are Ultra-Processed Foods Addictive?

1:02:10 - Carbon Diet Coach

1:03:10 - Nuance of Ultra-Processed Foods

1:07:35 - Negative Effects of UPFs Independent of Calories

1:13:09 - Criticism of Study Design

1:16:48 - Government Regulation

1:23:58 - Behavior Changes

1:29:37 - Animal vs Plant Based

1:33:08 - Personal Diet Habits

1:35:16 - Use Cases For UPFs

1:38:33 - The Practical Realities of Research

1:45:24 - What Have You Changed Your Mind On

1:49:14 - PhD Discussion

1:52:42 - Outro

SHOW NOTES

Creatine is SAFE, the verdict is in!

After decades of people claiming that creatine will wreck your kidneys, liver, & various other claims, a new study has put these myths to bed.

In my latest episode of the Dr. Layne Norton Podcast, I go DEEP on the most comprehensive dataset to date: a brand new meta-analysis by Kreider et al. (2025) which reviewed 250+ studies, covering over 26,000 participants, some lasting more than a decade, and examined nearly 50 potential side effects.

The verdict? Absolutely no evidence of harm.

I broke down the full paper, the methods, and what this means for athletes and everyday lifters in the latest episode of the podcast.

SPONSORS

• Outwork Nutrition - Evidence-Based Supplements to Support Your Hard Work: https://outworknutrition.com

• REPS Research Review: https://biolayne.com/reps

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

TIMESTAMPS

0:00:00 - Intro

0:01:33 - Meta Analysis Overview

0:02:14 - Creatine is NOT a Steroid

0:03:10 - ATP

0:05:13 - Creatine from Body and Food

0:06:05 - Creatine Non-Responders

0:06:27 - Creatine Dose

0:07:10 - Creatine Benefits

0:10:18 - Outwork Nutrition

0:11:46 - Interesting Associations

0:13:48 - Safety Questions

0:15:03 - Importance of Placebo

0:17:05 - Study Methods

0:20:05 - Study Results

0:26:08 - REPS Research Review

0:26:57 - Hair Loss

0:29:04 - Creatine is Safe and Effective

0:30:54 - Types of Creatine

0:36:54 - Creatine for Kids

0:38:50 - Recommendations

0:39:39 - Outro

SHOW NOTES

https://biolayne.com/podcasts/dr-layne-norton-podcast/study-deep-dive-creatine-is-safe-episode-13

Is sugar really to blame for the obesity epidemic? In this episode, I break down one of the most common nutrition myths. Using evidence from epidemiology, randomized controlled trials, and meta-analyses, Layne explains why sugar and high fructose corn syrup aren’t the independent culprits they’re often made out to be. Instead, he reveals what the research actually says about calories, metabolism, and how oversimplified narratives mislead the public. If you’ve ever been told “sugar is poison,” this episode will challenge your perspective with science, not fear.

SPONSORS

• REPS Research Review: https://biolayne.com/reps

• Carbon Diet Coach – Achieve your goals with Carbon’s adaptive macro coaching app: https://joincarbon.com/podcast

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

TIMESTAMPS

0:00:00 - Intro

0:02:49 - Research Funding and Bias

0:14:52 - Previous Beliefs on Sugar

0:15:31 - Types of Sugar

0:17:42 - Previous Beliefs on HFCS

0:19:37 - Leptin

0:23:56 - Gary Taubes

0:24:33 - REPS

0:25:22 - Carbohydrate Insulin Model of Obesity

0:27:42 - The Case for Sugar Causing Obesity

0:30:08 - The Moment I Started to Change My Mind

0:32:29 - Ice Cream

0:34:18 - Researching Sugar

0:39:15 - Mechanisms vs Outcomes

0:41:10 - Classic Study

0:42:28 - Mark Haub Twinkie Diet

0:45:46 - Carbon Diet Coach

0:46:46 - Metabolic Health

0:48:03 - Glycemic Index

0:49:51 - Sugar Intake vs Calorie Intake

0:52:30 - Sugar Addiction

0:54:21 - Let's Be Clear

0:56:36 - Data Over Feelings

SHOW NOTES

https://biolayne.com/podcasts/dr-layne-norton-podcast/did-sugar-cause-the-obesity-epidemic-episode-12

Building muscle isn’t just about aesthetics — it’s about survival. 💪

In this episode of The Dr. Layne Norton Podcast, I break down why muscle is the most underrated organ of health. You’ll hear how it lowers your risk of cardiovascular disease, cancer, infections, Alzheimer’s, and depression — while also protecting against falls, fractures, and the effects of aging.

We’ll dive into:

- How muscle acts like an endocrine organ, releasing myokines that fight disease and slow tumor growth.

- Why more muscle means longer life, better quality of life, and faster recovery if you get sick.

- The myth that you “can’t build muscle after a certain age” — and why it’s total BS.

- How just 50 minutes of resistance training a week can change your health trajectory.

If you want to live longer, feel stronger, and age on your own terms, this is the episode you don’t want to skip.

SPONSORS

• Workout Builder – Customized training programs for all experience levels: https://biolayne.com/workout-builder

• Team Biolayne – One-On-One Coaching: https://biolayne.com/online-coaching

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

TIMESTAMPS

0:00:00 - Intro

0:02:18 - Muscle for Vanity

0:03:39 - Cultural Perception of Muscles

0:06:13 - Women in the Gym

0:08:11 - Muscle for Health

0:10:34 - Sarcopenia

0:15:28 - Insulin Sensitivity

0:22:59 - Workout Builder

0:23:54 - Sink Metaphor

0:26:07 - Organ of Health

0:28:11 - Quality of Life

0:32:35 - Cardiovascular Disease Mortality

0:36:35 - Cancer Mortality

0:42:44 - Other Mortality

0:44:45 - Risk of Disease

0:49:22 - Mental Health

0:56:19 - Pain & Injuries

0:57:35 - Team Biolayne

0:58:26 - Wasting Diseases

1:00:59 - Anyone Can Build Muscle

1:03:20 - Outro

SHOW NOTES

https://biolayne.com/podcasts/dr-layne-norton-podcast/why-you-should-try-to-build-muscle-episode-11

Learn how to build muscle from the world's most renowned researcher on muscle growth, Professor Brad Schoenfeld. In this absolute masterclass, Dr. Schoenfeld lays out the non-negotiables for muscle growth, what matters most, what matters least, and how to practically implement these recommendations. If you care about building muscle, you do not want to miss this episode.

SPONSORS

• Workout Builder – Customized training programs for all experience levels: https://biolayne.com/workout-builder

• REPS Research Review: https://biolayne.com/reps

LAYNE'S COMPANIES

Carbon Diet Coach: https://joincarbon.com/podcast

Outwork Nutrition: https://outworknutrition.com

REPS Research Review: https://biolayne.com/reps

Workout Builder: https://biolayne.com/workout-builder

Team Biolayne: https://biolayne.com/online-coaching

Physique Coaching Academy: https://physiquecoachingacademy.com

FOLLOW LAYNE

http://www.facebook.com/laynenorton

http://www.twitter.com/biolayne

http://www.instagram.com/biolayne

FOLLOW BRAD

https://www.instagram.com/bradschoenfeldphd

http://www.twitter.com/bradschoenfeld

TIMESTAMPS

0:00:00 - Intro

0:03:20 - How Brad Got Started

0:08:24 - Vanity vs Health

0:14:46 - Muscle Quality

0:16:54 - Muscle and Insulin Resistance

0:22:00 - Most Important Thing for Hypertrophy

0:23:38 - Training to Failure

0:34:51 - Misinformation on Social Media

0:39:02 - Mechanical Tension

0:46:21 - Training Volume

0:52:24 - Workout Builder

0:54:45 - Dose Response

0:59:27 - Overtraining

1:07:19 - Muscle Damage and Soreness

1:14:35 - Mechanisms vs Outcomes

1:19:52 - Cortisol

1:21:15 - Acute vs Chronic

1:24:04 - Mechanisms vs Outcomes

1:25:43 - REPS Research Review

1:26:32 - Research on Volume

1:34:01 - Training Frequency

1:40:06 - Range of Motion

1:46:27 - Intensity Tricks

1:50:32 - Rep Cadence

1:58:03 - Exercise Selection

2:04:43 - Final Question

2:13:53 - Outro

SHOW NOTES

https://biolayne.com/podcasts/dr-layne-norton-podcast/how-to-build-muscle-masterclass-with-professor-brad-schoenfeld-episode-10