Iron Culture presented by MASS

In this episode, Eric Trexler and Eric Helms explore the energetic cost of building human skeletal muscle, discussing recent research, practical implications, and misconceptions about muscle growth and energy expenditure. Relevant papers: https://pubmed.ncbi.nlm.nih.gov/31482093/ https://pubmed.ncbi.nlm.nih.gov/37914977/ https://www.biorxiv.org/content/10.64898/2026.08.17.745156v1.full.pdf Catch new Iron Culture episodes every Tuesday at 5:30 pm eastern time! Be sure to use code "MRR10" for 10% off your order at elitefts.com Iron Culture is proudly presented by the MASS Research Review massresearchreview.com Chapters 00:00 Introduction 01:52 Powerlifting shout-out 11:55 Introduction to new paper on energetic cost of building muscle 20:01 Components of muscle tissue building and their energy costs 22:59 Practical implications of the 3500 calorie rule 30:05 The five additive components of muscle growth energy cost 33:49 Variability in individual energy expenditure responses 40:12 Limitations and future directions in research 50:10 Summary and concluding thoughts

Trexler and Helms dig into Helms's new MASS article, "Are studies on untrained lifters irrelevant to trained lifters?" It's built around a new umbrella review by Andy Fry and colleagues. The recurring internet claim is that most exercise research is done on untrained people, so a trained lifter is "built different" and the findings don't apply. The hosts unpack why that's mostly wrong. They start with the messy problem of defining how "trained" someone is. Then they discuss Fry's review, which reports that roughly 70% of resistance training study participants are sedentary or untrained, with fewer than 500 out of nearly 19,000 participants counting as genuinely well-trained. But the key focus of the episode is that this doesn't invalidate the research: what makes a beginner grow more will also make an advanced lifter grow more — the difference is rate, not mechanism. Iron Culture is proudly presented by the MASS Research Review. Mostly because Helms and Trex are co-owners. massresearchreview.com If you're in the market for some new (ultra-high-quality) gym gear or apparel, be sure to use code "MRR10" for a 10% discount over at elitefts.com If you'd like to submit a question for a future episode, head over to: massresearchreview.com/ironculture Chapters 0:00 Intro 8:25 The article: do untrained studies apply? 11:31 What does "trained" even mean? 22:26 How researchers try to define training status 25:51 Fry's approach & the McKay tiers 28:07 A review of reviews: mapping the literature 32:24 The finding: 70% untrained 37:46 Is that actually a problem? 43:44 Where meta-analyses fall short 51:27 Dose, stimulus & the maintenance threshold 58:27 Realistic rates of progress & goal-setting 1:14:51 Wrap-up: you don't need perfect

A methods-focused episode about how muscle and body-composition measurements can mislead you when reading the research. The main event is a new Balshaw and colleagues paper concluding that ultrasound muscle thickness is a poor index of MRI-measured muscle growth. Trexler and Helms argue this shouldn't be read as "throw out all ultrasound research" — the real culprit is that muscle thickness is a crude one-dimensional snapshot with measurement error large enough to swamp the small changes seen in typical short studies, whereas MRI captures growth in more dimensions with better fidelity. They walk through why comparing across different dimensions and different devices matters, what researchers can do about it (bigger doses, larger samples, multiple measurements), and use the famous "sleep restriction kills your gains by 60%" study as an example of over-reading a tiny difference in ten people. The second half turns to DEXA. Prompted by someone confused that DEXA fat mass didn't line up with the 3,500-calorie rule, they explain DEXA's three-compartment model, why it measures fat mass rather than adipose tissue, and why lean soft tissue readings are so sensitive to hydration. The practical upshot: don't build your worldview on a kilogram of day-to-day DEXA noise, be cautious using DEXA to estimate energy status, and understand that flattening a three-dimensional body into a two-dimensional scan introduces real limits. They close with an extended, tongue-in-cheek bit about trademarking "muscle journey" dimensions. Iron Culture is proudly presented by the MASS Research Review. Mostly because Helms and Trex are co-owners. massresearchreview.com If you're in the market for some new (ultra-high-quality) gym gear or apparel, be sure to use code "MRR10" for a 10% discount over at elitefts.com If you'd like to submit a question for a future episode, head over to: massresearchreview.com/ironculture Chapters 0:00 Intro 5:57 The paper: is ultrasound a poor muscle-growth measure? 18:04 What muscle thickness actually captures 25:38 Measurement error vs. a tiny signal 31:16 Different dimensions, different devices 37:52 What researchers should do about it 39:26 Case study: does sleep loss "kill gains"? 47:28 On to DEXA: where this started 53:26 How DEXA works & why fat mass ≠ adipose tissue 1:02:15 Why methods don't always agree 1:11:06 Water weight & the whooshing scale 1:16:43 Estimating energy status from DEXA 1:19:36 Wrap-up

Join Steve Hall and Eric Helms as they explore the nuances of bodybuilding, nutrition, and training strategies. From caffeine timing and body composition tracking to posing techniques and mental models, this conversation offers practical insights for athletes and enthusiasts aiming to optimize their performance and physique. Iron Culture is presented by the MASS Research Review massresearchreview.com If you're in the market for some new gym gear or apparel, be sure to use code "MRR10" for a 10% discount at elitefts.com Chapters 00:00 Morning Rituals: Caffeine Choices and Preferences 02:43 Caffeine Cycling: Strategies for Bodybuilding Performance 05:19 Caffeine and Sleep: Finding the Right Balance 08:27 Diet Sodas: The Hidden Caffeine Dilemma 10:52 Navigating Post-Show Eating: The Recovery Phase 13:53 Protein Intake: Debating the Optimal Amount 16:45 Training vs. Nutrition: Prioritizing Muscle Gain 19:26 Understanding Protein Recommendations: Context Matters 22:17 The Importance of Training Intensity 25:06 Blue Light Blockers: Effects on Sleep Quality 35:20 Blue Light Blockers and Sleep Quality 37:11 Body Weight and Recovery Insights 39:11 Stage Weight and Body Composition Changes 41:34 Tracking Progress: Measurements and Photos 45:10 The Importance of Posing in Bodybuilding 50:39 Online Coaching and Posing Techniques

This episode begins with a discussion about the importance of scientific rigor in fitness research and science communication. After that, hosts Eric Trexler and Eric Helms discuss the relationship between skeletal structure and muscle growth, including whether or not your bone structure can predict how much muscle you gain in response to training or your maximum level of muscularity. Iron Culture is proudly presented by the MASS Research Review (massresearchreview.com) If you're in the market for some high-quality gym gear or apparel, be sure to support our friends at elitefts.com and use code "MRR10" for a 10% discount. Chapters 00:00 Intro 11:19 Expert Creep and Science Communication 21:22 Responsibly Expanding Your Domain of Expertise 31:42 Exploring Bone Structure and Muscle Growth 32:51 Study Overview: Bone Characteristics and Hypertrophy 41:13 Interpreting the results of a new study 47:50 Methodological nuances 58:30 Hypertrophy versus total muscularity 01:02:48 Finding the right sport for your frame and bone structure 01:12:23 Practical applications

Join us for an in-depth discussion with Steve Hall & Eric Helms on supplement testing, polygraph use in bodybuilding, sleep optimization, and the power of acceptance in training and life. This episode offers practical insights for natural bodybuilders and fitness enthusiasts looking to optimize health, performance, and mental resilience. If you're in the market for some new lifting gear or apparel, be sure to use code "MRR10" at elitefts.com for a 10% discount Chapters 00:00 Introduction and Connection 02:09 Understanding Supplementation and Third-Party Testing 08:04 Microplastics and Health Concerns 09:58 The Importance of Third-Party Testing for Competitors 15:59 The Risks of Supplements and Marketing Influence 21:56 Polygraphs in Natural Bodybuilding 30:06 Navigating False Positives in Polygraph Testing 37:11 The Stress of Competition and Polygraph Testing 38:45 Personal Struggles with Lifestyle Constraints 40:59 Sleep Quality Challenges and Optimization 43:41 Navigating Workload and Recovery 45:01 Injury Management and Training Adjustments 50:14 Mental Strategies for Performance and Recovery 58:56 Acceptance and Its Role in Bodybuilding and Life

In this episode, Eric Helms and Eric Trexler explore the complexities of food labeling, energy absorption, and the impact of food choices on energy balance. They discuss a recent lawsuit against David protein bars, delve into scientific research on metabolizable energy, and practical strategies for dieting and food selection. If you're in the market for some new lifting gear or apparel, be sure to use code "MRR10" at elitefts.com for a 10% discount Chapters 00:00 Introduction and Updates 08:16 The David Protein Bar Lawsuit 21:43 Labeling Complications and Nutritional Misunderstandings 25:25 The Impact of TEF, Fiber, and Resistant Starches 34:00 The Impact of the Specific Food Matrix 37:22 More Research on Dietary Intake Versus Absorption 40:06 Nuances Behind Calories In vs Calories Out 47:00 Tracking Variable Foods Versus Keeping Food Choices Consistent (IIFYM/Flexible Dieting Implications) 57:06 The Case for "Eating Clean" Within a Flexible Dieting Framework

In this episode, Steve Hall and Eric Helms discuss the evolution of their podcast, the importance of community feedback, and the dynamics of online culture. They delve into personality traits that influence social media behavior, the misconceptions surrounding pop science, and the significance of evidence-based practices in coaching and bodybuilding. Eric shares insights about his new role in academia and the responsibilities that come with it, while also exploring the 1% factors that can lead to success in bodybuilding. The conversation wraps up with a discussion on supplements, health practices, and the importance of being informed about one's health. If you're in the market for some lifting gear or apparel, please consider supporting our friends over at elitefts.com (and use code "MRR10" for a 10% discount!) Chapters 00:00 Introduction and Naming the Podcast 02:48 The Psychology of Online Fitness Culture 05:39 Personality Traits and Social Media Engagement 08:05 Debunking Pop Psychology Myths 10:48 The Evolution of Online Coaching 13:49 Eric's New Role and Responsibilities 16:40 Leadership in Academia 19:22 The Structure of Academic Institutions 22:10 Reflections on Leadership and Responsibility 37:07 The Pursuit of the 1% in Bodybuilding 40:04 Training Philosophy and Personal Context 43:01 Evaluating Training Volume and Time Management 45:41 Investing in Muscle Growth: The Cost-Benefit Analysis 49:27 The Role of Supplements and Nutrition 55:39 Final Thoughts and Future Discussions