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.com

Chapters 0:00 Introduction 3:45 Today's Show 5:38 Creatine for Women: Marketing vs. Science 9:09 Debunking Myths: Creatine Levels in Women 17:59 Issues With Creatine Gummies 24:48 Creatine Washout and Cycling 30:00 Creatine and Subcutaneous Water Retention 36:32 Training for Bone Health 46:22 Loading Recommendations for Bone Remodeling 50:05 Nuances in Bone Research 1:01:11 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.com

Keep up-to-date with Dr. Lewis and his projects: https://drmarclewis.com/ Instagram: @marctlewis Twitter/X: @marctlewis

Chapters 00:00 Introduction to Sports Science in Football 01:47 What Does a Sports Scientist Do? 7:26 From Data to Decisions 11:00 Navigating the Data Overload 23:13 Applied Data Versus Peer-Reviewed Evidence 27:20 Applying Sports Science Insights to Strength Coaching 34:46 The Reality of Overtraining in Elite Sport Versus General Fitness 45:17 The Extremes of Human Performance 51:01 Unique Needs of Elite Athletes 56:45 The Current State (and Future) of Sports Science in America 1:09:46 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.com

Time stamps 00:00 Introduction (College Football & Powerlifting News) 04:25 Partnership with Elite FTS and Personal Experiences 11:50 Collagen Supplementation: Debates and Research Overview 35:37 Power Development: Training Volumes and Frequencies 49:00 Creatine: Dosage, Urination Frequency, and Cognitive Effects 1:03:18 Muscular Endurance: Training Insights 01:08:34 Hypertrophy and Athletic Performance 1:19:00 Creatine During Peak Week 1:19:58 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.com

Chapters 00:00 Intro 09:10 The Debate on Muscle Size and Strength 12:30 New Research on Muscle Strength and Size 20:45 Exploring Sex Differences in Muscle Training 26:40 The Hierarchy of Evidence in Research 32:00 Relationships Between Strength And Muscle Size 36:40 Lifting For Sport: History And Changing Cultural Norms 39:00 Back To The Study Results (Understanding Sex Differences in Strength Gains) 42:15 Nuances of Statistical Analysis: Relationships Between Strength And Muscle Size 54:10 Aside About Collegiate Sports In USA 56:50 Causal Discovery Analysis in Strength Research 1:08:00 Summary and Conclusions: The Role of Muscle Growth in Strength Gains 1:21:45 Listener Question: Sample Sizes in Exercise Science 1:27:10 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.

Chapters 00:00 Introduction and Guest Introduction 06:25 The PhD Journey and Team Dynamics 11:32 Dissertation Overview and Research Focus 18:43 Research Methodology and Individual Variability 26:50 Understanding Individual Response Variation in Training 32:09 Study Design: Isolating Variables in Training Responses 37:33 The Importance of Replication in Research 42:40 Findings 53:41 Limitations and Implications of the Study 01:00:17 Genetics and Individual Response Variability 01:02:59 The Dose-Response Relationship in Training 01:06:25 Shifting Perspectives on Training Individualization 01:11:00 The Role of Sports Science in Coaching 01:19:51 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 Introduction 01:11  Preview of next week's episode (non-responders, hyper-responders, etc) 07:01 Trex's surgery update 12:11 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 Prep 59:16 Chrono Nutrition and Sleep Quality 01:11:28 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.com

Time stamps 0:00 Intro 4:18 New issue of the MASS Research Review 10:42 Helms contest prep update 13:15 The history of the ECA stack and supplement regulation 30:07 Ephedra vs Ephedrine  35:31 Why people took ephedrine / ECA stack 36:30 Trends in PED use over time 45:00 Research on the ECA stack 50:58 Banning lifters for stimulant use 53:15 Effects of ephedrine + caffeine on metabolism and fat loss 1:02:44 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 yohimbine 1:32:58 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 website

https://www.jimstoppani.com/

Time stamps

0:00 Intro

3:22 Jim’s education

14:18 Jim’s transition to the muscle magazine industry

30:44 Jim’s bodybuilding dot com days

44:52 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 science 1:00:04 – 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.com https://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 Guests 5:57 The Science of (Male) Attractiveness 10:39 Evolutionary Underpinnings of Male Attractiveness 13:53 Distorted Perceptions of Attractiveness (In the Fitness World) 20:10 The Irony of Pursuing Attractiveness 22:22 Body-Fat and Optimized Health 24:18 Surprising Article Feedback 28:50 Unrealistic Body Standards and Gender Perceptions 32:49 Achieving the Outcome Versus Doing Hard Things 35:07 Attractiveness is More Than Body Shape/Size 37:48 The Science of Being Cool 47:19 Matching Exercise To Personality Types

References:

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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.

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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%2Fxge0001799

https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2025.1587472/full