Building muscle doesn’t happen in the gym alone. In Part 2 of this series, I break down the nutrition and supplementation variables that actually matter for maximizing muscle growth and which ones are overhyped or misunderstood.

We start with protein: how much you really need, why protein quality matters, the role of essential amino acids and leucine in stimulating muscle protein synthesis, and how protein distribution across the day can influence results. I also dive into how protein needs change with age, why older adults require higher per-meal and daily protein intakes, and practical recommendations to offset age-related anabolic resistance.

From there, we cover energy intake: how caloric deficits impair muscle protein synthesis, why massive surpluses don’t accelerate lean mass gains in trained lifters, and how to think about maintenance versus small surpluses depending on training status.

Finally, I break down the supplements that are actually supported by strong evidence — including creatine and whey protein: what they do, how they work, and how to use them effectively. We also cover common factors that can sabotage muscle growth, like smoking, excessive alcohol, poor sleep, and inappropriate use of NSAIDs or high-dose antioxidants.

If you want a clear, science-based framework for using nutrition and supplements to support muscle growth, without gimmicks or misinformation, then this episode is for you.

SPONSORS

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

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

0:05:02 - Most Important Thing

0:05:35 - Protein Structure

0:07:09 - Protein Digestion

0:09:55 - Protein RDA

0:10:40 - Nitrogen Balance

0:12:24 - Muscle Turnover

0:14:09 - Amino Acids

0:19:35 - mTOR

0:23:12 - Carbon Diet Coach

0:24:12 - How Much Protein

0:29:56 - Protein Distribution

0:39:08 - Protein and Aging

0:45:04 - Protein Quality

0:50:50 - Outwork Nutrition

0:52:17 - Calories

1:01:23 - Supplements

1:05:16 - Things to Avoid

1:13:10 - Outro

SHOW NOTES

https://biolayne.com/podcasts/dr-layne-norton-podcast

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 Fibers

0:10:48...

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 - Cell Journal