Iron Culture presented by MASS

In this episode of MASS Office Hours Live, Dr. Eric Trexler and Dr. Mike Zourdos kick off the show by discussing a recent controversial Instagram post about a retracted cold bath/cold shower study, emphasizing the importance of understanding the hierarchy of evidence and the challenges of effectively communicating retractions to the public. The hosts then share some of their past fitness and nutrition recommendations they now wish they could retract. The episode then transitions into a rapid-fire Q&A segment, addressing a wide range of listener questions. Topics covered include the optimal resistance training frequency for muscle growth and whether it should differ between bulking and cutting phases, the potential benefits of hydrolyzed whey protein compared to regular whey, the effects of Tylenol on performance and gains, the superiority of training to failure versus leaving reps in reserve for hypertrophy, a potential link between appetite suppression and longer rest periods during a calorie deficit, how to train for maximum power production in athletic contexts, and much more. Throughout the discussion, Trexler and Zourdos provide evidence-based insights and practical recommendations to help listeners navigate these common fitness and nutrition questions. You can download the MASS time-efficient training guide here: https://massresearchreview.com The MASS crew goes live for Office Hours every Wednesday night at 7pm eastern time. Be sure to join us for a future episode! If you'd like to submit a question ahead of time, please use this link: https://massresearchreview.com/office-hours/ Time stamps: 0:00 - Intro 3:40 - Trexler discusses a recent controversial Instagram post about a retracted cold bath/cold shower study and the hierarchy of evidence 19:47 - Zourdos shares fitness/nutrition recommendations he previously made that he now wishes he could retract, related to concurrent training 22:55 - Trexler shares his own past recommendations he would retract, including protein timing and refeeds/diet breaks 27:36 - Question about optimal resistance training frequency and whether it should differ between bulking and cutting phases 33:48 - Question about whether hydrolyzed whey protein provides any benefits compared to regular whey protein 39:24 - Does all of our meaningful muscle growth occur in the first few months of training? 57:07 - Practical question about program design 59:17 - Practical question about running frequency 1:01:53 - Practical question about size of energy surplus during a bulking/massing phase 1:03:52 - Does cardio improve recovery from resistance training? 1:06:41 - Practical question about compensatory acceleration training 1:09:42 - Question about whether Tylenol (acetaminophen) ingestion affects performance and gains 1:11:56 - Question about whether training to failure is truly superior for hypertrophy compared to leaving a few reps in reserve 1:18:34 - Question about a potential link between appetite suppression and longer rest periods between sets while in a calorie deficit 1:21:22 - Question about how to train for maximum power production for athletic purposes

In this episode of Iron Culture, Eric Trexler welcomes back Eric Helms, who clarifies recent misunderstandings about his commitment to the iron game. Helms shares insights from his recent travels, including a global education event with TechnoGym in Bali, and discusses the importance of cultural experiences in fitness education. The conversation also covers strategies for managing jet lag during international travel, the mechanics of hypertrophy, and the significance of community in fitness. As Helms prepares for upcoming competitions, he reflects on his journey in bodybuilding and the evolving landscape of the fitness industry.Need some lifting gear? Use our discount code (MRR10) over at www.elitefts.comChapters00:00 Welcome Back to Iron Culture03:50 Clarifying Misunderstandings09:51 Eric's Upcoming Competition14:52 Travel Adventures and Experiences23:42 Jet Lag and Nutrition Strategies32:00 Engaging with the Fitness Community39:39 The Rise of Science in Fitness48:50 Hypertrophy and Leverage Data01:20:46 Wrapping Up and Future Plans

In this episode of Iron Culture, Eric Trexler is joined by Dr. Lauren Colenso-Semple to discuss various topics in fitness, particularly focusing on creatine supplementation, female-oriented creatine marketing, the rising popularity of creatine gummies, and several creatine myths. They discuss the importance of understanding the science behind creatine and debunk common misconceptions before moving on to discuss the role of exercise in bone health and fracture prevention.Need some lifting gear? Use our discount code (MRR10) over at www.elitefts.comChapters0:00 Introduction3:45 Today's Show5:38 Creatine for Women: Marketing vs. Science9:09 Debunking Myths: Creatine Levels in Women17:59 Issues With Creatine Gummies24:48 Creatine Washout and Cycling30:00 Creatine and Subcutaneous Water Retention36:32 Training for Bone Health46:22 Loading Recommendations for Bone Remodeling50:05 Nuances in Bone Research1:01:11 Dietary Considerations for Bone Health

In this episode of Iron Culture, Eric Trexler interviews Dr. Marc Lewis, the director of Applied Sports Science for the Houston Texans. They discuss the role of sports scientists in maximizing athlete performance through data collection, management, and analysis. Marc shares insights on the day-to-day responsibilities of a sports scientist, the importance of understanding athlete load and stress, and the evolution of sports science in the NFL. They also explore the future of sports science careers and provide advice for aspiring sports scientists.Need some lifting gear? Use our discount code (MRR10) over at www.elitefts.comKeep up-to-date with Dr. Lewis and his projects:https://drmarclewis.com/Instagram: @marctlewisTwitter/X: @marctlewisChapters00:00 Introduction to Sports Science in Football01:47 What Does a Sports Scientist Do?7:26 From Data to Decisions11:00 Navigating the Data Overload23:13 Applied Data Versus Peer-Reviewed Evidence27:20 Applying Sports Science Insights to Strength Coaching34:46 The Reality of Overtraining in Elite Sport Versus General Fitness45:17 The Extremes of Human Performance51:01 Unique Needs of Elite Athletes56:45 The Current State (and Future) of Sports Science in America1:09:46 Building a Career in Sports Science

In this episode of Iron Culture, hosts Eric Trexler and Eric Helms discuss recent developments in college football and powerlifting, in addition to introducing their partnership with Elite FTS. The conversation shifts to a Q&A session where they address various topics, including collagen supplementation, creatine dosage, and the relationship between muscular endurance and strength. They also provide practical tips for reducing food focus during dieting and discuss the impact of hypertrophy on athletic performance.Need some lifting gear? Use our discount code (MRR10) over at www.elitefts.comTime stamps00:00 Introduction (College Football & Powerlifting News)04:25 Partnership with Elite FTS and Personal Experiences11:50 Collagen Supplementation: Debates and Research Overview35:37 Power Development: Training Volumes and Frequencies49:00 Creatine: Dosage, Urination Frequency, and Cognitive Effects1:03:18 Muscular Endurance: Training Insights01:08:34 Hypertrophy and Athletic Performance1:19:00 Creatine During Peak Week1:19:58 Dieting Strategies and Food Focus

In this episode of Iron Culture, hosts Eric Trexler and Eric Helms discuss various topics including the ongoing debate about the relationship between muscle growth and strength gains. They discuss brand new findings from the largest and longest-running study on resistance training, explore the implications of "apparent" sex differences in strength gains, and emphasize the need for nuanced statistical analysis in understanding the factors that contribute to strength gains and observed sex differences.Want to read a thorough analysis of the article we discussed in this episode (and many more)? Support the show by joining the MASS Community at massresearchreview.comChapters00:00 Intro09:10 The Debate on Muscle Size and Strength12:30 New Research on Muscle Strength and Size20:45 Exploring Sex Differences in Muscle Training26:40 The Hierarchy of Evidence in Research32:00 Relationships Between Strength And Muscle Size36:40 Lifting For Sport: History And Changing Cultural Norms39:00 Back To The Study Results (Understanding Sex Differences in Strength Gains)42:15 Nuances of Statistical Analysis: Relationships Between Strength And Muscle Size54:10 Aside About Collegiate Sports In USA56:50 Causal Discovery Analysis in Strength Research1:08:00 Summary and Conclusions: The Role of Muscle Growth in Strength Gains1:21:45 Listener Question: Sample Sizes in Exercise Science1:27:10 Outro

In this episode of Iron Culture, hosts Eric Helms and Michael Zourdos engage with Dr. Zac Robinson to discuss his dissertation research on the effects of resistance training volume on muscle adaptations. The conversation delves into the complexities of individual responses to training, the importance of research design, and the implications of findings for coaching practices. They emphasize the need for caution in interpreting data and the evolving nature of sports science, highlighting the significance of collaboration and flexibility in training approaches.Chapters00:00 Introduction and Guest Introduction06:25 The PhD Journey and Team Dynamics11:32 Dissertation Overview and Research Focus18:43 Research Methodology and Individual Variability26:50 Understanding Individual Response Variation in Training32:09 Study Design: Isolating Variables in Training Responses37:33 The Importance of Replication in Research42:40 Findings53:41 Limitations and Implications of the Study01:00:17 Genetics and Individual Response Variability01:02:59 The Dose-Response Relationship in Training01:06:25 Shifting Perspectives on Training Individualization01:11:00 The Role of Sports Science in Coaching01:19:51 Future Directions in Resistance Training Research

In this episode, Drs Trexler and Helms discuss various topics including updates on Eric's surgery, the valuable (but very modest) effects of protein intake on muscle gains, incontinence after contest prep, the relationship between sleep quality and nutrient timing, the recent ban on smelling salts in the NFL, and more.Time stamps:00:00 Introduction01:11 Preview of next week's episode (non-responders, hyper-responders, etc)07:01 Trex's surgery update12:11 Discussion on Protein Meta-Analyses and Research Updates (how much does protein intake actually matter for gains?)33:10 Why meta-analyses differ from RCTs in terms of "expiration dates"44:15 The Impact of Training vs. Nutrition (for muscle growth)51:41 Q&A: Supplementation for Lifters (and Specifically Vegans Who Lift)55:49 Incontinence, Increased Urine Output, and Contest Prep59:16 Chrono Nutrition and Sleep Quality01:11:28 The Role of Smelling Salts in Sports Performance (and Football)

In this episode of Iron Culture, Helms and Trex have a lengthy discussion about the ECA stack and yohimbine. The history, the mechanisms, the regulatory changes, the practical applications – you name it, they cover it. Don’t miss this episode if you have an interest in fat loss, stimulants, or dietary supplementation in general.Also, be sure to check out the newest issue of the MASS Research Review! Learn more at massresearchreview.comTime stamps0:00 Intro4:18 New issue of the MASS Research Review10:42 Helms contest prep update13:15 The history of the ECA stack and supplement regulation30:07 Ephedra vs Ephedrine 35:31 Why people took ephedrine / ECA stack36:30 Trends in PED use over time45:00 Research on the ECA stack50:58 Banning lifters for stimulant use53:15 Effects of ephedrine + caffeine on metabolism and fat loss1:02:44 What does aspirin really add to the ECA stack?1:13:00 Do NSAIDs blunt hypertrophy?1:21:25 How yohimbine works (and yohimbe vs yohimbine distinction)1:31:10 Regulatory status of yohimbine1:32:58 Practical applications

Back when Trex was a 14 year old, his wrestling coach noticed his passion for training and nutrition. This coach took Trex under his wing, and they started absorbing and applying as much information as they could. Their source material, almost exclusively, was the content produced by Dr. Jim Stoppani – primarily from magazine articles, but also from the totally novel medium of online video content. Jim was a jacked PhD with tons of “in the trenches” experience - back in 2005 that was a very rare combination, and there’s no question that people like Jim led the way for the next generation of “bodybuilding academics” like Helms and Trex. Jim has made a huge mark on the fitness industry. Perhaps his most impressive feat is maintaining his impact and relevance as the industry has fundamentally transformed itself multiple times. Jim was the face of some of the biggest muscle magazines (in their prime), one of the most recognizable content creators when bodybuilding dot com was THE place for online fitness, and way ahead of the curve when it comes to building your own platform and leveraging mobile fitness applications. In this episode of Iron Culture, the Erics have a great chat with Dr. Stoppani about how the industry (and science communication more broadly) has evolved over the last 25-30 years. To learn more about Jim and support his work, check out his social media channels and his websitehttps://www.jimstoppani.com/ Time stamps0:00 Intro3:22 Jim’s education14:18 Jim’s transition to the muscle magazine industry30:44 Jim’s bodybuilding dot com days44:52 Fitness content creation in the age of social media: the good, the bad, and the ugly

Join hosts Eric Trexler and Eric Helms as they explore the potential "replication crisis" in exercise science, drawing parallels to the well-documented crisis in psychology. In this episode, they delve into the challenges of replicating research findings, the perils of placing too much confidence in singular studies, the importance of cautious interpretation of new studies, and the value of meta-analyses in understanding true effect sizes. Whether you're a seasoned lifter or new to the world of evidence-based practice, this conversation offers valuable insights into making informed decisions about your training.Time stamps:00:00 – Introduction (and Helms’ travel updates)17:29 - Replication Crisis in Psychology: Discussion on the replication crisis observed in psychology and its implications.32:45 – What is “replication”44:36 – Results of “reproducibility project” in exercise science1:00:04 – Why are replication rates so low in exercise science?1:27:24 – What does this mean for “evidence-based fitness” and application of exercise science?Relevant links:www.massresearchreview.comhttps://pubmed.ncbi.nlm.nih.gov/26315443/https://pubmed.ncbi.nlm.nih.gov/40522610/

In this episode of Iron Culture, Dr. Eric Trexler and Dr. Lauren Colenso-Semple discuss science related to attractiveness, coolness, and personality type. They explore scientific studies on the factors associated with perceived attractiveness and "coolness," discussing body fat percentages and societal perceptions. The conversation shifts to how personality traits appear to predict workout preferences and engagement in fitness, then they debate the importance of matching exercise to individual characteristics.Time stamps:00:00 Introduction to Iron Culture and Guests5:57 The Science of (Male) Attractiveness10:39 Evolutionary Underpinnings of Male Attractiveness13:53 Distorted Perceptions of Attractiveness (In the Fitness World)20:10 The Irony of Pursuing Attractiveness22:22 Body-Fat and Optimized Health24:18 Surprising Article Feedback28:50 Unrealistic Body Standards and Gender Perceptions32:49 Achieving the Outcome Versus Doing Hard Things35:07 Attractiveness is More Than Body Shape/Size37:48 The Science of Being Cool47:19 Matching Exercise To Personality TypesReferences:Xia F, Sauciuvenaite J, Bissland R, Hambly C, Starr-Vaanholt L, Faries MD, et al. The relationship between body fatness and physical attractiveness in males. Personality and Individual Differences. 2025 Sep 1;243:113240.de Jager S, Coetzee N, Coetzee V. Facial Adiposity, Attractiveness, and Health: A Review. Front Psychol. 2018 Dec 21;9:2562.Brierley ME, Brooks KR, Mond J, Stevenson RJ, Stephen ID. The Body and the Beautiful: Health, Attractiveness and Body Composition in Men’s and Women’s Bodies. PLoS One. 2016;11(6):e0156722.Sorokowski P, Kościński K, Sorokowska A, Huanca T. Preference for Women’s Body Mass and Waist-to-Hip Ratio in Tsimane’ Men of the Bolivian Amazon: Biological and Cultural Determinants. PLoS One. 2014 Aug 22;9(8):e105468.Tovée MJ, Cornelissen PL. Female and male perceptions of female physical attractiveness in front-view and profile. Br J Psychol. 2001 May;92(Pt 2):391–402.Jayedi A, Khan TA, Aune D, Emadi A, Shab-Bidar S. Body fat and risk of all-cause mortality: a systematic review and dose-response meta-analysis of prospective cohort studies. Int J Obes (Lond). 2022 Sep;46(9):1573–81.Hu J, Chen X, Yang J, Giovannucci E, Lee DH, Luo W, et al. Association between fat mass and mortality: analysis of Mendelian randomization and lifestyle modification. Metabolism. 2022 Nov;136:155307.Ramlau-Hansen CH, Thulstrup AM, Nohr EA, Bonde JP, Sørensen TIA, Olsen J. Subfecundity in overweight and obese couples. Hum Reprod. 2007 Jun;22(6):1634–7.Wei S, Schmidt MD, Dwyer T, Norman RJ, Venn AJ. Obesity and menstrual irregularity: associations with SHBG, testosterone, and insulin. Obesity (Silver Spring). 2009 May;17(5):1070–6.Liu Y, Hu X, Xiong M, Li J, Jiang X, Wan Y, et al. Association of BMI with erectile dysfunction: A cross-sectional study of men from an andrology clinic. Front Endocrinol (Lausanne). 2023;14:1135024.https://psycnet.apa.org/doiLanding?doi=10.1037%2Fxge0001799https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2025.1587472/full

In this episode of Iron Culture, Eric Helms interviews Dr. Stian Larsen, who shares his journey from powerlifting to becoming a researcher in exercise science. They discuss the intricacies of biomechanics, the importance of understanding squat techniques, and the latest research findings on muscle hypertrophy and resistance profiles. Stian emphasizes the need for practical applications in training and the significance of collaboration in research. The conversation also touches on future research directions and the role of education in advancing the field of strength training.Time stamps0:00 Introduction4:33 Stian's Journey in Powerlifting and Coaching16:00 Biomechanics and the Sticking Point in Squats 23:56 Understanding Muscle Forces and Training Strategies33:04 Transitioning to Hypertrophy Research35:43 Research on Muscle Length and Hypertrophy48:58 Practical Applications of Research Findings50:02 Biceps Research Findings and Surprises1:03:28 Practical Applications of Research Findings1:04:53 Quadriceps Hypertrophy Study Results1:22:27 Lateral Raises and Resistance Profiles

In this episode of Iron Culture, the Erics provide some updates, corrections, and clarifications related to their recent episode exploring the science of microplastics. After that they take a brief moment to celebrate the 100th issue of the MASS Research Review, then answer listener questions on topics including: tasty meat alternatives, programming supersets, scaling dietary variables for very small/short individuals, the pros & cons of "extended release" caffeine formulations, the utility & shortcomings of BMI as a health metric, and more.MASS is celebrating its 100th issue, but it's never to late to join in on the fun! Learn more at massresearchreview.comAlso, don't miss Iron Culture's sister podcast, ⁨@fpfpodcast⁩ hosted by MASS's very own Eric Trexler and Dr. Lauren Colenso-SempleTime stamps (coming soon):0:00 Intro0:58 Revisiting microplastics (updates, corrections, and clarifications)25:08 MASS celebrates 100th issue34:00 Well-wishes for bodybuilding legend Ronnie Coleman41:37 Tasty meat alternatives47:12 Programming supersets49:23 Scaling dietary variables for very small/short individuals57:10 The utility & shortcomings of BMI as a health metric1:05:03 Individual response variation to training1:16:12 The pros & cons of "extended release" caffeine formulations

In this episode of Iron Culture, Dr. Eric Helms talks about his forthcoming article in the MASS Research Review covering the purported harms of high-protein diets. This isn’t your typical oversimplified dunk-fest that readily dismisses concerns about high-protein diets. Instead, Helms reviews a thorough paper that reviews common concerns in detail and assessed their plausibility in an objective manner. The claims include: Claim 1 – protein reduces lifespanClaim 2 – protein makes bones weakerClaim 3 – protein harms kidneysClaim 4 – protein causes diabetesAfter that, Dr. Eric Trexler discusses a recent Instagram thread that pulled him into arguments against his will. The post was about his recent article on ketogenic diets and seed oils – two topics that are always bound to attract some controversy and heated debate. This conversation discusses the strengths and limitations of different types of scientific research and also touches on bias, objectivity, and the process of seeking the truth with an open mind.Time stamps:0:00 Intro3:00 Helms’ new article about the purported harms of high-protein diets19:25 Claim 1 – protein reduces lifespan27:48 Claim 2 – protein makes bones weaker43:38 Claim 3 – protein harms kidneys50:53 Claim 4 – protein causes diabetes57:22 Trex’s social media beefs – keto and seed oils1:03:40 Types of observational studies1:08:35 Seeking truth versus defending biases1:17:32 Limitations versus fatal flaws1:24:19 Limitations of RCTs (randomized controlled trials)1:32:23 Wrapping up

In this episode, the hosts discuss various aspects of bodybuilding prep, including caloric intake, metabolic adaptation, and the impact of extreme dieting. They explore historical studies that provide insights into these phenomena and discuss practical strategies for weight loss. The conversation transitions to powerlifting, specifically the recent IPF Worlds, highlighting the competitive dynamics and standout performances in the event. In this conversation, Eric Helms highlights impressive performances and battles in various weight classes. He emphasizes the growth of the sport and the challenges faced by lifters, particularly in extreme conditions. The subsequent Q&A covers the balance between powerlifting and bodybuilding, exercise order for hypertrophy, and the relationship between energy balance and recovery. Additionally, the practicality and effectiveness of using weighted vests for exercise are examined, providing insights into their potential benefits and drawbacks.Time stamps:00:00 Introduction and Helms' Updates on Bodybuilding Prep01:50 Caloric Intake and Metabolic Adaptation05:35 Extreme Cases of Metabolic Adaptation: Insights from Historical Studies25:26 IPF Worlds Recap44:44 Programming for Powerlifting and Bodybuilding (Simultaneously)48:26 Exercise Order and Hypertrophy01:00:23 Energy Balance and Recovery01:05:44 The Pros and Cons of Weighted Vests

In this episode of Iron Culture, the Erics begin by discussing Helms' prep updates and the standout performances from the recent powerlifting World Champions. The conversation also touches on body composition and attractiveness, highlighting the misconceptions in the fitness industry regarding ideal body fat levels. After that they take a deep dive into the strategies of cutting weight in various sports, comparing the approaches of powerlifting, bodybuilding, and combat sports. Finally, they explore the differences in weight cutting techniques across different sports, emphasizing the importance of planning and strategy for optimal performance.Time stamps:00:00 Helms Prep Update and World Powerlifting Highlights15:07 Body Composition, Attractiveness, Evolution, and the Fitness Industry31:16 Trexler's Take On Comparing Weight Cuts in Different Sports (Powerlifting, Bodybuilding, Combat Sports)40:32 Helms' Take On Comparing Weight Cuts in Different Sports (Powerlifting, Bodybuilding, Combat Sports)57:11 Electrolyte Management and Hydration Techniques1:03:05 Final Thoughts on Weight Management and Performance

In this episode of the Iron Culture Podcast, the Erics discuss various topics including updates on Helms' contest prep vlog, a preview of the upcoming Powerlifting World Championships, misconceptions surrounding TRT, the effects of cold exposure, and the concept of lean mass hyper responders. They also discuss the importance of (and misconceptions surrounding) women's health research, and engage in a Q&A session addressing questions about energy expenditure, body composition, and more. Time stamps:00:00 Introduction and Updates02:59 Powerlifting World Championships Preview07:55 New MASS issue; TRT misconceptions16:50 Cold Exposure and Its Misconceptions18:00 Lean Mass Hyper Responders (and resulting chaos)31:20 Women's Health and Fitness Research46:24 Understanding Training Status in Research52:52 Core Strengthening and building general athleticism59:03 Debunking Myths Around Posture and Anterior Pelvic Tilt01:01:50 Evaluating BIA and BIS for Body Composition01:10:48 Reconciling Energy Expenditure Models in Active Populations

What's the deal with microplastics? Where do they come from? Are they in our bodies? If so, are they harmful? Also, what's the deal with microwaving Tupperware and other plastic containers?This episode is all about plastics - what we know, what we don't know, and what you can do about it.Key reference:https://pmc.ncbi.nlm.nih.gov/articles/PMC11800385/Time stamps:0:00 Intro7:20 What are microplastics and where to they come from?16:40 How much microplastic is in our bodies? Does it seem to be a problem?32:05 What can you do about microplastics?41:50 What can you do about Tupperware and other food storage options?1:06:51 Related Q&A1:20:48 Wrapping up

In this episode of Iron Culture presented by MASS, Dr. Eric Helms and Dr. Eric Trexler dive into a wide-ranging discussion covering updates on the long-awaited 3rd edition of the Muscle & Strength Pyramids, the writing process at MASS, and their recent frustrations with pseudoscientific claims in fitness and health.They dissect recent content related to eccentric training, ketogenic diets, LDL cholesterol myths, and the fine line between critical thinking and cynicism. Plus, they tackle rapid-fire audience questions on deloading, protein intake, training at short vs. long muscle lengths, and more.Timestamps0:00 Intro1:43 Muscle and Strength Pyramids Update7:00 Why the Erics are extra snippy (about popular pseudoscience) in the upcoming issue of MASS12:00 Keto diets and LDL (new research)20:20 Why pseudoscience gains popularity24:00 Cynicism vs. Skepticism32:09 Paradigm shifts37:02 Should I deload every 4 weeks?46:02 Shortened vs. lengthened muscle training50:37 High protein diets and kidney health question53:21 Muscle imbalances after injury rehab 61:29 Why do we speak about the thermic effect of feeding so imprecisely? Why not manipulate it with high degree of specificity?74:17 Hypertrophy rep ranges74:56 Exercise science study design versus real-world questions84:54 What's up with microplastics? 93:24 Wrapping up