Barbell Medicine Podcast

A 22 year old soccer player with no symptoms walks into a clinic for a routine sports physical and walks out being told to quit his sport.Dr. Baraki takes this mystery case blind and we hand him the pieces one at a time: the EKG, the echocardiogram, the cardiac MRI, the Holter monitor, the treadmill test and the genetic panel. Half of them come back completely normal. Play along and commit to an answer before the reveal, because there is a point in this case where most people would change theirs.Then, the discussion about whether the restriction he was given was the right call, what the evidence on that says today compared with what it said for the previous 40 years, and why two doctors looking at the same numbers can reasonably land in different places.And then screening. Should an EKG should be mandatory for amateur athletes? All this and more, on this episode of the Barbell Medicine Podcast.Timestamps00:00 A 22-year-old needs a form signed02:16 The history and exam05:49 Reading his EKG 13:13 The echo and the MRI18:26 The rest of the workup, and Austin commits to a diagnosis24:02 Patient course27:54 What his care team decided29:45 How much the heart changes with training36:45 A second case that went differently41:52 Should a finding like this end a career45:47 Should an EKG be mandatory for amateur athletes55:59 What would actually move the needleResourcesBuy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/Free Vital 5 Action PlanNew Barbell Medicine Hybrid 5K and 10K Run + Lift ProgramsBarbell Medicine coaching and templates: https://www.barbellmedicine.comGet early access, ad-free listening, and exclusive content here: https://barbellmedicine.supercast.com/1. Marques JP, Freitas A, Abecasis J. Beware of regression of electrocardiographic abnormalities on detraining: it may not always mean "athlete's heart." Rev Port Cardiol (Engl Ed). 2021;40(10):801.e1-801.e6. doi:10.1016/j.repce.2021.10.012. PMID 34857120.2. Pelliccia A, Maron BJ, Culasso F, et al. Clinical significance of abnormal electrocardiographic patterns in trained athletes. Circulation. 2000;102(3):278-284. doi:10.1161/01.cir.102.3.278. PMID 10899089.3. Papadakis M, Carre F, Kervio G, et al. The prevalence, distribution, and clinical outcomes of electrocardiographic repolarization patterns in male athletes of African/Afro-Caribbean origin. Eur Heart J. 2011;32(18):2304-2313. doi:10.1093/eurheartj/ehr140. PMID 21613263.4. Schnell F, Riding N, O'Hanlon R, et al. Recognition and significance of pathological T-wave inversions in athletes. Circulation. 2015;131(2):165-173. doi:10.1161/CIRCULATIONAHA.114.011038. PMID 25583053.5. Olivotto I, Oreziak A, Barriales-Villa R, et al. Mavacamten for treatment of symptomatic obstructive hypertrophic cardiomyopathy (EXPLORER-HCM): a randomised, double-blind, placebo-controlled, phase 3 trial. Lancet. 2020;396(10253):759-769. doi:10.1016/S0140-6736(20)31792-X. PMID 32871100.6. Maron MS, Masri A, Nassif ME, et al. Aficamten for symptomatic obstructive hypertrophic cardiomyopathy. N Engl J Med. 2024;390(20):1849-1861. doi:10.1056/NEJMoa2401424. PMID 38739079.7. Myers J, Prakash M, Froelicher V, Do D, Partington S, Atwood JE. Exercise capacity and mortality among men referred for exercise testing. N Engl J Med. 2002;346(11):793-801. doi:10.1056/NEJMoa011858. PMID 11893790.8. Ommen SR, Mital S, Burke MA, et al. 2020 AHA/ACC guideline for the diagnosis and treatment of patients with hypertrophic cardiomyopathy: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2020;142(25):e558-e631. doi:10.1161/CIR.0000000000000937. PMID 33215931.9. Lopes LR, Ho CY, Elliott PM. Genetics of hypertrophic cardiomyopathy: established and emerging implications for clinical practice. Eur Heart J. 2024;45(30):2727-2734. doi:10.1093/eurheartj/ehae421. PMID 38984491.10. Ingles J, Goldstein J, Thaxton C, et al. Evaluating the clinical validity of hypertrophic cardiomyopathy genes. Circ Genom Precis Med. 2019;12(2):e002460. doi:10.1161/CIRCGEN.119.002460. PMID 30681346.11. Pelliccia A, Maron BJ, Spataro A, Proschan MA, Spirito P. The upper limit of physiologic cardiac hypertrophy in highly trained elite athletes. N Engl J Med. 1991;324(5):295-301. doi:10.1056/NEJM199101313240504. PMID 1824720.12. Spirito P, Pelliccia A, Proschan MA, et al. Morphology of the "athlete's heart" assessed by echocardiography in 947 elite athletes representing 27 sports. Am J Cardiol. 1994;74(8):802-806. doi:10.1016/0002-9149(94)90439-1. PMID 7942554.13. Powers JM, Lim MY, Achebe MO, et al. American Society of Hematology 2026 guidelines for diagnosis of iron deficiency. Blood Adv. Published online August 24, 2026. doi:10.1182/bloodadvances.2025015950. PMID 42747316.14. Basavarajaiah S, Boraita A, Whyte G, et al. Ethnic differences in left ventricular remodeling in highly-trained athletes: relevance to differentiating physiologic left ventricular hypertrophy from hypertrophic cardiomyopathy. J Am Coll Cardiol. 2008;51(23):2256-2262. doi:10.1016/j.jacc.2007.12.061. PMID 18534273.15. Riding NR, Sharma S, McClean G, Adamuz C, Watt V, Wilson MG. Impact of geographical origin upon the electrical and structural manifestations of the black athlete's heart. Eur Heart J. 2019;40(1):50-58. doi:10.1093/eurheartj/ehy521. PMID 30169663.16. Kebed KY, Bos JM, Anavekar NS, Mulvagh SL, Ackerman MJ, Ommen SR. Hypertrophic cardiomyopathy, athlete's heart, or both: a case of hypertrophic cardiomyopathy regression. Circ Cardiovasc Imaging. 2015;8(7):e003312. doi:10.1161/CIRCIMAGING.115.003312. PMID 26162782.17. Pelliccia A, Maron BJ, De Luca R, Di Paolo FM, Spataro A, Culasso F. Remodeling of left ventricular hypertrophy in elite athletes after long-term deconditioning. Circulation. 2002;105(8):944-949. doi:10.1161/hc0802.104534. PMID 11864923.18. Ommen SR, Ho CY, Asif IM, et al. 2024 AHA/ACC/AMSSM/HRS/PACES/SCMR guideline for the management of hypertrophic cardiomyopathy: a report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines. Circulation. 2024;149(23):e1239-e1311. doi:10.1161/CIR.0000000000001250. PMID 38718139.19. Lampert R, Ackerman MJ, Marino BS, et al. Vigorous exercise in patients with hypertrophic cardiomyopathy. JAMA Cardiol. 2023;8(6):595-605. doi:10.1001/jamacardio.2023.1042. PMID 37195701.20. Pelliccia A, Caselli S, Pelliccia M, et al. Clinical outcomes in adult athletes with hypertrophic cardiomyopathy: a 7-year follow-up study. Br J Sports Med. 2020;54(16):1008-1012. doi:10.1136/bjsports-2019-100890. PMID 32532845.21. Kim JH, Baggish AL, Levine BD, et al. Clinical considerations for competitive sports participation for athletes with cardiovascular abnormalities: a scientific statement from the American Heart Association and American College of Cardiology. Circulation. 2025;151(11):e716-e761. doi:10.1161/CIR.0000000000001297. PMID 39973614.22. Corrado D, Basso C, Pavei A, Michieli P, Schiavon M, Thiene G. Trends in sudden cardiovascular death in young competitive athletes after implementation of a preparticipation screening program. JAMA. 2006;296(13):1593-1601. doi:10.1001/jama.296.13.1593. PMID 17018804.23. Harmon KG, Zigman M, Drezner JA. The effectiveness of screening history, physical exam, and ECG to detect potentially lethal cardiac disorders in athletes: a systematic review/meta-analysis. J Electrocardiol. 2015;48(3):329-338. doi:10.1016/j.jelectrocard.2015.02.001. PMID 25701104.24. Baggish AL, Hutter AM, Wang F, et al. Cardiovascular screening in college athletes with and without electrocardiography: a cross-sectional study. Ann Intern Med. 2010;152(5):269-275. doi:10.7326/0003-4819-152-5-201003020-00004. PMID 20194232.25. Drezner JA, Owens DS, Prutkin JM, et al. Electrocardiographic screening in National Collegiate Athletic Association athletes. Am J Cardiol. 2016;118(5):754-759. doi:10.1016/j.amjcard.2016.06.004. PMID 27496294.26. Williams EA, Pelto HF, Toresdahl BG, et al. Performance of the American Heart Association (AHA) 14-point evaluation versus electrocardiography for the cardiovascular screening of high school athletes: a prospective study. J Am Heart Assoc. 2019;8(14):e012235. doi:10.1161/JAHA.119.012235. PMID 31286819.27. Steinvil A, Chundadze T, Zeltser D, et al. Mandatory electrocardiographic screening of athletes to reduce their risk for sudden death: proven fact or wishful thinking? J Am Coll Cardiol. 2011;57(11):1291-1296. doi:10.1016/j.jacc.2010.10.037. PMID 21392644.28. Halkin A, Steinvil A, Rosso R, Adler A, Rozovski U, Viskin S. Preventing sudden death of athletes with electrocardiographic screening: what is the absolute benefit and how much will it cost? J Am Coll Cardiol. 2012;60(22):2271-2276. doi:10.1016/j.jacc.2012.09.003. PMID 23194938.29. Marijon E, Tafflet M, Celermajer DS, et al. Sports-related sudden death in the general population. Circulation. 2011;124(6):672-681. doi:10.1161/CIRCULATIONAHA.110.008979. PMID 21788587.30. Finocchiaro G, Papadakis M, Robertus JL, et al. Etiology of sudden death in sports: insights from a United Kingdom regional registry. J Am Coll Cardiol. 2016;67(18):2108-2115. doi:10.1016/j.jacc.2016.02.062. PMID 27151341.31. Harmon KG, Drezner JA, Maleszewski JJ, et al. Pathogeneses of sudden cardiac death in National Collegiate Athletic Association athletes. Circ Arrhythm Electrophysiol. 2014;7(2):198-204. doi:10.1161/CIRCEP.113.001376. PMID 24585715.32. Drezner JA, Rao AL, Heistand J, Bloomingdale MK, Harmon KG. Effectiveness of emergency response planning for sudden cardiac arrest in United States high schools with automated external defibrillators. Circulation. 2009;120(6):518-525. doi:10.1161/CIRCULATIONAHA.109.855890. PMID 19635968.33. Grubic N, Hill B, Phelan D, Baggish A, Dorian P, Johri AM. Bystander interventions and survival after exercise-related sudden cardiac arrest: a systematic review. Br J Sports Med. 2022;56(7):410-416. doi:10

A Halloween story about a man who does every wellness protocol, then an honest grading of each one. Dr. Jordan Feigenbaum tells the story of Dale Mercer, Unit 4471, who lives through a fully optimized Sunday in the year 2049: morning light panels, cold plunges, a 31-capsule supplement tray, grey-market peptides, methylene blue, an eccentric-only lifting machine, a protein IV timed to the anabolic window, sleep and readiness scores, a glucose sensor, mouth tape, Zone 2 with lactate pricks, and a 174-degree sauna.Then Jordan grades each one on a zero-to-five pumpkin scale. He covers what the studies actually tested, where the evidence is thin or tied to the companies selling the product, and the few places with real risk, like methylene blue with antidepressants and mouth taping with a blocked nose. The takeaway is plain: lift weights in a challenging way, do conditioning that improves your fitness, sleep enough, and eat a health-promoting diet in the right amount. Most of the rest is optional.The story is inspired by Rick Sieman's 1973 motorcycle magazine column "Sunday Morning Ride … 1984."Timestamps 00:00 WELLNESS ad 00:26 Sunday Morning Protocol 2049 11:23 Where this episode came from, and the pumpkin scale 12:45 Morning sunlight and cold plunges19:44 Supplements: magnesium, lion's mane, NAD, antler velvet, creatine 25:21 Peptides and methylene blue 30:27 Eccentric overload, slow tempo, and the anabolic window 34:40 Sleep trackers, HRV readiness scores, and CGMs 41:56 Mouth tape, Zone 2, and saunas 47:44 What actually worksResourcesBuy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/Free Vital 5 Action PlanNew Barbell Medicine Hybrid 5K and 10K Run + Lift ProgramsBarbell Medicine coaching and templates: https://www.barbellmedicine.comGet early access, ad-free listening, and exclusive content here: https://barbellmedicine.supercast.com/Creatine: Benefits, Side Effects & Safe Consumption: https://www.barbellmedicine.com/blog/what-is-creatine/Barbell Medicine Guide to Protein: https://www.barbellmedicine.com/blog/barbell-medicine-protein-recommendations/How to Measure, Use and Improve Your Heart Rate Variability: https://www.barbellmedicine.com/blog/heart-rate-variability-hrv/Burke TM, Markwald RR, Chinoy ED, et al. Combination of light and melatonin time cues for phase advancing the human circadian clock. Sleep. 2013;36(11):1617-1624. doi:10.5665/sleep.3110Auger RR, Burgess HJ, Emens JS, Deriy LV, Thomas SM, Sharkey KM. Clinical practice guideline for the treatment of intrinsic circadian rhythm sleep-wake disorders: advanced sleep-wake phase disorder (ASWPD), delayed sleep-wake phase disorder (DSWPD), non-24-hour sleep-wake rhythm disorder (N24SWD), and irregular sleep-wake rhythm disorder (ISWRD). An update for 2015: an American Academy of Sleep Medicine clinical practice guideline. J Clin Sleep Med. 2015;11(10):1199-1236. doi:10.5664/jcsm.5100van Maanen A, Meijer AM, van der Heijden KB, Oort FJ. The effects of light therapy on sleep problems: a systematic review and meta-analysis. Sleep Med Rev. 2016;29:52-62. doi:10.1016/j.smrv.2015.08.009Thompson A, Batterham AM, Jones H, Gregson W, Scott D, Atkinson G. The practicality and effectiveness of supplementary bright light for reducing jet-lag in elite female athletes. Int J Sports Med. 2013;34(7):582-589. doi:10.1055/s-0032-1331160Pjrek E, Friedrich ME, Cambioli L, et al. The efficacy of light therapy in the treatment of seasonal affective disorder: a meta-analysis of randomized controlled trials. Psychother Psychosom. 2020;89(1):17-24. doi:10.1159/000502891Burns AC, Saxena R, Vetter C, Phillips AJK, Lane JM, Cain SW. Time spent in outdoor light is associated with mood, sleep, and circadian rhythm-related outcomes: a cross-sectional and longitudinal study in over 400,000 UK Biobank participants. J Affect Disord. 2021;295:347-352. doi:10.1016/j.jad.2021.08.056Manson JE, Cook NR, Lee IM, et al. Vitamin D supplements and prevention of cancer and cardiovascular disease. N Engl J Med. 2019;380(1):33-44. doi:10.1056/NEJMoa1809944Srámek P, Simecková M, Janský L, Savlíková J, Vybíral S. Human physiological responses to immersion into water of different temperatures. Eur J Appl Physiol. 2000;81(5):436-442. doi:10.1007/s004210050065Cain T, Brinsley J, Bennett H, Nelson M, Maher C, Singh B. Effects of cold-water immersion on health and wellbeing: a systematic review and meta-analysis. PLoS One. 2025;20(1):e0317615. doi:10.1371/journal.pone.0317615Buijze GA, Sierevelt IN, van der Heijden BC, Dijkgraaf MG, Frings-Dresen MH. The effect of cold showering on health and work: a randomized controlled trial. PLoS One. 2016;11(9):e0161749. doi:10.1371/journal.pone.0161749Cameron BE, Steele J, Bradley WJ, et al. Post-exercise recovery methods: a systematic review and meta-analysis. SportRxiv. Preprint posted September 19, 2026. doi:10.51224/SportRxiv.1070Roberts LA, Raastad T, Markworth JF, et al. Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. J Physiol. 2015;593(18):4285-4301. doi:10.1113/JP270570Piñero A, Burke R, Augustin F, et al. Throwing cold water on muscle growth: a systematic review with meta-analysis of the effects of postexercise cold water immersion on resistance training-induced hypertrophy. Eur J Sport Sci. 2024;24(2):177-189. doi:10.1002/ejsc.12074Liu G, Weinger JG, Lu ZL, Xue F, Sadeghpour S. Efficacy and safety of MMFS-01, a synapse density enhancer, for treating cognitive impairment in older adults: a randomized, double-blind, placebo-controlled trial. J Alzheimers Dis. 2016;49(4):971-990. doi:10.3233/JAD-150538Lopresti AL, Smith SJ. The effects of magnesium L-threonate (Magtein) on cognitive performance and sleep quality in adults: a randomised, double-blind, placebo-controlled trial. Front Nutr. 2025;12:1729164. doi:10.3389/fnut.2025.1729164Schuster J, Cycelskij I, Lopresti A, Hahn A. Magnesium bisglycinate supplementation in healthy adults reporting poor sleep: a randomized, placebo-controlled trial. Nat Sci Sleep. 2025;17:2027-2040. doi:10.2147/NSS.S524348Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults: a systematic review & meta-analysis. BMC Complement Med Ther. 2021;21(1):125. doi:10.1186/s12906-021-03297-zMori K, Inatomi S, Ouchi K, Azumi Y, Tuchida T. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial. Phytother Res. 2009;23(3):367-372. doi:10.1002/ptr.2634Surendran G, Saye J, Binti Mohd Jalil S, et al. Acute effects of a standardised extract of Hericium erinaceus (Lion’s Mane mushroom) on cognition and mood in healthy younger adults: a double-blind randomised placebo-controlled study. Front Nutr. 2025;12:1405796. doi:10.3389/fnut.2025.1405796Prokopidis K, Moriarty F, Bahat G, McLean J, Church DD, Patel HP. The effect of nicotinamide mononucleotide and riboside on skeletal muscle mass and function: a systematic review and meta-analysis. J Cachexia Sarcopenia Muscle. 2025;16(3):e13799. doi:10.1002/jcsm.13799Chen F, Zhou D, Kong AP, et al. Effects of nicotinamide mononucleotide on glucose and lipid metabolism in adults: a systematic review and meta-analysis of randomised controlled trials. Curr Diab Rep. 2024;25(1):4. doi:10.1007/s11892-024-01557-zBrakedal B, Skeie GO, Derad C, et al. Nicotinamide riboside for patients with early-stage Parkinson disease: the NOPARK randomized clinical trial. JAMA. Published online 2026. doi:10.1001/jama.2026.18828Sleivert G, Burke V, Palmer C, et al. The effects of deer antler velvet extract or powder supplementation on aerobic power, erythropoiesis, and muscular strength and endurance characteristics. Int J Sport Nutr Exerc Metab. 2003;13(3):251-265. doi:10.1123/ijsnem.13.3.251Syrotuik DG, MacFadyen KL, Harber VJ, Bell GJ. Effect of elk velvet antler supplementation on the hormonal response to acute and chronic exercise in male and female rowers. Int J Sport Nutr Exerc Metab. 2005;15(4):366-385. doi:10.1123/ijsnem.15.4.366Cox HD, Eichner D. Detection of human insulin-like growth factor-1 in deer antler velvet supplements. Rapid Commun Mass Spectrom. 2013;27(19):2170-2178. doi:10.1002/rcm.6678Delpino FM, Figueiredo LM, Forbes SC, Candow DG, Santos HO. Influence of age, sex, and type of exercise on the efficacy of creatine supplementation on lean body mass: a systematic review and meta-analysis of randomized clinical trials. Nutrition. 2022;103-104:111791. doi:10.1016/j.nut.2022.111791Prokopidis K, Giannos P, Triantafyllidis KK, Kechagias KS, Forbes SC, Candow DG. Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials. Nutr Rev. 2023;81(4):416-427. doi:10.1093/nutrit/nuac064Xu C, Bi S, Zhang W, Luo L. The effects of creatine supplementation on cognitive function in adults: a systematic review and meta-analysis. Front Nutr. 2024;11:1424972. doi:10.3389/fnut.2024.1424972Wilding JPH, Batterham RL, Calanna S, et al. Once-weekly semaglutide in adults with overweight or obesity. N Engl J Med. 2021;384(11):989-1002. doi:10.1056/NEJMoa2032183Jastreboff AM, Aronne LJ, Ahmad NN, et al. Tirzepatide once weekly for the treatment of obesity. N Engl J Med. 2022;387(3):205-216. doi:10.1056/NEJMoa2206038Poolton JT, Minett J, Kazmi A. Human evidence for BPC-157 in orthopaedic and regenerative medicine: a systematic review of efficacy and safety. Acta Orthop Belg. 2026;92(3). doi:10.52628/92.3.15837Reichel C, Gmeiner G, Thevis M. Detection of black market follistatin 344. Drug Test Anal. 2019;11(11-12):1675-1697. doi:10.1002/dta.2741ClinicalTrials.gov. Search results for BPC-157. National Library of Medicine. Accessed October 2026. https://clinicaltrials.gov/search?term=BPC-157Rodriguez P, Zhou W, Barrett DW, et al. 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How much cardio should you do, and does more of it ever become harmful? Cardiorespiratory fitness keeps improving with training load and nobody has found a ceiling. Getting fitter keeps lowering mortality risk as far out as anyone has measured. The one dose dependent harm that survives scrutiny is atrial fibrillation, and it shows up around six to seven hours a week of hard endurance training sustained for years.This episode goes through the Danish jogging study behind the “fast running is as deadly as sitting on the couch” headlines and why two deaths in forty people can’t carry it, the much larger datasets that found no harm signal, and what changes when somebody measures fitness on a treadmill instead of asking people about minutes. Then atrial fibrillation, coronary calcium and heart scarring in lifelong endurance athletes, the sudden cardiac arrest numbers from 29 million race finishers, whether cardio interferes with lifting, fuel handling, weight loss and metabolic compensation, and bone density in cyclists. It closes with a rewritten version of the cardio guidelines, including volume, intensity, progression, and the fitness and health targets the real guidelines leave out.Timestamps00:00 The jogging J-curve and the headlines02:42 The Danish study, its confidence interval, and what a MET measures08:02 Better measurement: 15 check-ins and fitness on a treadmill12:51 Atrial fibrillation: the dose, the mechanism, and stroke risk22:06 Coronary calcium and heart scarring in masters athletes25:58 The marathon death story and cardiac arrest rates29:08 How much training it takes to keep getting fitter34:12 Does cardio interfere with your lifting gains39:52 Flux, the athlete's paradox, and liver fat44:12 Cardio, weight loss, and metabolic compensation51:13 Bone density in cyclists and energy availability57:51 Writing the cardio guidelinesResourcesBuy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/Free Vital 5 Action PlanNew Barbell Medicine Hybrid 5K and 10K Run + Lift ProgramsBarbell Medicine coaching and templates: https://www.barbellmedicine.comGet early access, ad-free listening, and exclusive content here: https://barbellmedicine.supercast.com/1. Schnohr P, O'Keefe JH, Marott JL, Lange P, Jensen GB. Dose of jogging and long-term mortality: the Copenhagen City Heart Study. J Am Coll Cardiol. 2015. doi:10.1016/j.jacc.2014.11.0232. Arem H, Moore SC, Patel A, et al. Leisure time physical activity and mortality: a detailed pooled analysis of the dose-response relationship. JAMA Intern Med. 2015. doi:10.1001/jamainternmed.2015.05333. Lee DH, Rezende LFM, Joh HK, et al. Long-term leisure-time physical activity intensity and all-cause and cause-specific mortality: a prospective cohort of US adults. Circulation. 2022. doi:10.1161/CIRCULATIONAHA.121.0581624. Mandsager K, Harb S, Cremer P, Phelan D, Nissen SE, Jaber W. Association of cardiorespiratory fitness with long-term mortality among adults undergoing exercise treadmill testing. JAMA Netw Open. 2018. doi:10.1001/jamanetworkopen.2018.36055. Ekelund U, Tarp J, Steene-Johannessen J, et al. Dose-response associations between accelerometry measured physical activity and sedentary time and all cause mortality: systematic review and harmonised meta-analysis. BMJ. 2019. doi:10.1136/bmj.l45706. Saulicz A, Abernethy D, Wraith D. Can too much exercise kill you? A systematic review of the risk of a cardiovascular event or death from long term strenuous exercise. Eur J Epidemiol. 2026. doi:10.1007/s10654-025-01353-37. Morganroth J, Maron BJ, Henry WL, Epstein SE. Comparative left ventricular dimensions in trained athletes. Ann Intern Med. 1975.8. Davies CL, Pallikadavath S, March DS, et al. Physical activity, atrial fibrillation and the dose-response relationship: a systematic review and meta-analysis. Eur J Prev Cardiol. 2026. doi:10.1093/eurjpc/zwag5359. Molina L, Mont L, Marrugat J, et al. Long-term endurance sport practice increases the incidence of lone atrial fibrillation in men: a follow-up study. Europace. 2008. doi:10.1093/europace/eun07110. Javed W, Botis I, Tomoaia R, et al. Clinical and cardiovascular magnetic resonance characteristics of veteran male endurance athletes with atrial fibrillation: VENTOUX-AF. J Am Heart Assoc. 2025. doi:10.1161/JAHA.125.04230811. Liu B, Pagan E, Beccarino N, Chang D, Dulmovits E, Beldner S. Voltage mapping and pulmonary vein isolation in master athletes with atrial fibrillation. Pacing Clin Electrophysiol. 2022;45(11):1338-1342. doi:10.1111/pace.1460212. Guasch E, Benito B, Qi X, et al. Atrial fibrillation promotion by endurance exercise: demonstration and mechanistic exploration in an animal model. J Am Coll Cardiol. 2013. doi:10.1016/j.jacc.2013.01.09113. Flannery MD, Canovas R, Janssens K, et al. Atrial fibrillation in former world-class rowers: role of environmental and genetic factors. Eur Heart J. 2025. doi:10.1093/eurheartj/ehaf36914. Johansen KR, Ranhoff AH, Sorensen E, et al. Risk of atrial fibrillation and stroke among older men exposed to prolonged endurance sport practice: a 10-year follow-up. The Birkebeiner Ageing Study and the Tromso Study. Open Heart. 2022;9(2). doi:10.1136/openhrt-2022-00215415. Apelland T, Letnes JM, Janssens K, et al. Arrhythmia burden, symptoms and quality of life in female and male endurance athletes with paroxysmal atrial fibrillation: a multicentre cohort study in Norway, Australia and Belgium. BMJ Open. 2025;15(8):e100496. doi:10.1136/bmjopen-2025-10049616. Merghani A, Maestrini V, Rosmini S, et al. Prevalence of subclinical coronary artery disease in masters endurance athletes with a low atherosclerotic risk profile. Circulation. 2017;136(2):126-137. doi:10.1161/CIRCULATIONAHA.116.02696417. Aengevaeren VL, Mosterd A, Braber TL, et al. Relationship between lifelong exercise volume and coronary atherosclerosis in athletes. Circulation. 2017;136(2):138-148. doi:10.1161/CIRCULATIONAHA.117.02783418. Kim JH, Rim AJ, Miller JT, et al. Cardiac arrest during long-distance running races. JAMA. 2025;333(19):1699-1707. doi:10.1001/jama.2025.302619. Montero D, Cathomen A, Jacobs RA, et al. Haematological rather than skeletal muscle adaptations contribute to the increase in peak oxygen uptake induced by moderate endurance training. J Physiol. 2015;593(20):4677-4688. doi:10.1113/JP27025020. Molmen KS, Almquist NW, Skattebo O. Effects of exercise training on mitochondrial and capillary growth in human skeletal muscle: a systematic review and meta-regression. Sports Med. 2025;55(1):115-144. doi:10.1007/s40279-024-02120-221. Church TS, Earnest CP, Skinner JS, Blair SN. Effects of different doses of physical activity on cardiorespiratory fitness among sedentary, overweight or obese postmenopausal women with elevated blood pressure: a randomized controlled trial. JAMA. 2007.22. Hickson RC. Interference of strength development by simultaneously training for strength and endurance. Eur J Appl Physiol Occup Physiol. 1980.23. Schumann M, Feuerbacher JF, Sunkeler M, et al. Compatibility of concurrent aerobic and strength training for skeletal muscle size and function: an updated systematic review and meta-analysis. Sports Med. 2022. doi:10.1007/s40279-021-01587-724. Lundberg TR, Feuerbacher JF, Sunkeler M, Schumann M. The effects of concurrent aerobic and strength training on muscle fiber hypertrophy: a systematic review and meta-analysis. Sports Med. 2022;52(10):2391-2403. doi:10.1007/s40279-022-01688-x25. Feuerbacher JF, Jacobs MW, Heumann P, Pareja-Blanco F, Hackney AC, Zacher J, Schumann M. Neuromuscular adaptations to same versus separate muscle-group concurrent aerobic and strength training in recreationally active males and females. Scand J Med Sci Sports. 2025;35(2):e70025. doi:10.1111/sms.7002526. Montero D, Lundby C. Refuting the myth of non-response to exercise training: 'non-responders' do respond to higher dose of training. J Physiol. 2017. doi:10.1113/JP27348027. Mezincescu AM, Rudd A, Cheyne L, et al. Comparison of intramyocellular lipid metabolism in patients with diabetes and male athletes. Nat Commun. 2024;15(1):3690. doi:10.1038/s41467-024-47843-y28. Keating SE, Hackett DA, Parker HM, et al. Effect of aerobic exercise training dose on liver fat and visceral adiposity. J Hepatol. 2015;63(1):174-182. doi:10.1016/j.jhep.2015.02.02229. Pearson RC, Cogan B, Garcia SA, Jenkins NT. Effect of prior exercise on postprandial lipemia: an updated meta-analysis and systematic review. Int J Sport Nutr Exerc Metab. 2022;32(6):501-518. doi:10.1123/ijsnem.2022-004330. Ross R, Hudson R, Stotz PJ, Lam M. Effects of exercise amount and intensity on abdominal obesity and glucose tolerance in obese adults: a randomized trial. Ann Intern Med. 2015. doi:10.7326/M14-118931. Westerterp KR, Meijer GA, Janssen EM, Saris WH, ten Hoor F. Long-term effect of physical activity on energy balance and body composition. Br J Nutr. 1992.32. Pontzer H, Trexler ET. The evidence for constrained total energy expenditure in humans and other animals. Curr Biol. 2026;36(4):1013-1025.e4. doi:10.1016/j.cub.2026.01.02533. Nichols JF, Palmer JE, Levy SS. Low bone mineral density in highly trained male master cyclists. Osteoporos Int. 2003;14(8):644-649.34. Nichols JF, Rauh MJ. Longitudinal changes in bone mineral density in male master cyclists and nonathletes. J Strength Cond Res. 2011;25(3):727-734. doi:10.1519/JSC.0b013e3181c6a11635. Olmedillas H, Gonzalez-Aguero A, Moreno LA, Casajus JA, Vicente-Rodriguez G. Cycling and bone health: a systematic review. BMC Med. 2012;10:168. doi:10.1186/1741-7015-10-16836. Abrahin O, Rodrigues RP, Marcal AC, Alves EA, Figueiredo RC, de Sousa EC. Swimming and cycling do not cause positive effects on bone mineral density: a systematic review. Rev Bras Reumatol. 2016. doi:10.1016/j.rbre.2016.02.01337. Keay N, Francis G, Hind K. Low energy availability assessed by a sport-specific questionnaire and clinical interview indicative of bone health, endocrine profile and cycling performance

How much resistance training do you actually need, and is there a point where more stops helping? We trace the "lift weights twice a week" recommendation back to the 1989 study it came from, which found that three days beat two, and to the citation loop that turned it into a guideline anyway. Then we go through the evidence on whether lifting is dangerous, including the heart, injury rates, and the J-shaped mortality curve, and work out where the dose-response actually saturates for strength, muscle mass, bone mineral density, and how your body handles fuel.The short answer is that almost every number in this literature marks where a benefit starts, and very little of it goes far enough to show where a benefit stops. We finish by writing the resistance training guideline the way we think it should be written, with target outcomes, a training dose, and testable targets.Timestamps 00:00 Where the "lift weights twice a week" rule came from 04:18 What actually counts as resistance training 06:56 Does lifting make your heart wall thicker 15:34 Anabolic steroids and the heart 19:16 Injury rates and cardiac arrest at the gym 22:03 How the lifting J-curve got made 28:05 ACSM audits its own recommendation 31:11 Strength: where the plateau actually sits 35:49 Why grip strength can't answer this 41:43 Muscle mass versus muscle function 44:50 Bone, and the turkey wing that settled the dose 49:50 Fuel handling, insulin sensitivity, and the clock 1:00:46 The 2018 guidelines, and how I would write themResourcesBuy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/New Barbell Medicine Hybrid 5K and 10K Run + Lift ProgramsBarbell Medicine coaching and templates: https://www.barbellmedicine.comGet early access, ad-free listening, and exclusive content here: https://barbellmedicine.supercast.com/Braith RW, Graves JE, Pollock ML, Leggett SL, Carpenter DM, Colvin AB. Comparison of 2 vs 3 days/week of variable resistance training during 10- and 18-week programs. Int J Sports Med. 1989;10(6):450-454. doi:10.1055/s-2007-1024942. PMID 2628366.American College of Sports Medicine. Position stand: the recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness in healthy adults. Med Sci Sports Exerc. 1990;22(2):265-274. PMID 2355825.Sandercock GRH, Moran J, Cohen DD. Who is meeting the strengthening physical activity guidelines by definition: a cross-sectional study of 253,423 English adults? PLoS One. 2022;17(5):e0267277. doi:10.1371/journal.pone.0267277. PMID 35507575.Shakespear-Druery J, De Cocker K, Biddle SJH, Gasevic D, Bennie JA. Assessment of muscle-strengthening exercise in public health surveillance for adults: a systematic review. Prev Med. 2021;148:106566. doi:10.1016/j.ypmed.2021.106566. PMID 33878352.Zhang Y, Lee DH, Rezende LFM, et al. Long-term resistance training with all-cause and cause-specific mortality: assessing dose-response and joint associations with aerobic physical activity. Br J Sports Med. 2026;60(12):874-883. doi:10.1136/bjsports-2025-110503. PMID 42230125.Morganroth J, Maron BJ, Henry WL, Epstein SE. Comparative left ventricular dimensions in trained athletes. Ann Intern Med. 1975;82(4):521-524. doi:10.7326/0003-4819-82-4-521. PMID 1119766.Naylor LH, George K, O'Driscoll G, Green DJ. The athlete's heart: a contemporary appraisal of the Morganroth hypothesis. Sports Med. 2008;38(1):69-90. doi:10.2165/00007256-200838010-00006. PMID 18081368.Myerson SG, Montgomery HE, World MJ, Pennell DJ. Left ventricular mass: reliability of M-mode and 2-dimensional echocardiographic formulas. Hypertension. 2002;40(5):673-678. doi:10.1161/01.hyp.0000036401.99908.db. PMID 12411461.Pelliccia A, Maron BJ, Spataro A, Proschan MA, Spirito P. The upper limit of physiologic cardiac hypertrophy in highly trained elite athletes. N Engl J Med. 1991;324(5):295-301. doi:10.1056/NEJM199101313240504. PMID 1824720.Spirito P, Pelliccia A, Proschan MA, et al. Morphology of the "athlete's heart" assessed by echocardiography in 947 elite athletes representing 27 sports. Am J Cardiol. 1994;74(8):802-806. doi:10.1016/0002-9149(94)90439-1. PMID 7942554.Pelliccia A, Spataro A, Caselli G, Maron BJ. Absence of left ventricular wall thickening in athletes engaged in intense power training. Am J Cardiol. 1993;72(14):1048-1054. doi:10.1016/0002-9149(93)90861-6. PMID 8213586.Spence AL, Naylor LH, Carter HH, et al. A prospective randomised longitudinal MRI study of left ventricular adaptation to endurance and resistance exercise training in humans. J Physiol. 2011;589(Pt 22):5443-5452. doi:10.1113/jphysiol.2011.217125. PMID 21969450.Utomi V, Oxborough D, Whyte GP, et al. Systematic review and meta-analysis of training mode, imaging modality and body size influences on the morphology and function of the male athlete's heart. Heart. 2013;99(23):1727-1733. doi:10.1136/heartjnl-2012-303465. PMID 23474689.Smit DL, Voogel AJ, den Heijer M, de Ronde W. Anabolic androgenic steroids induce reversible left ventricular hypertrophy and cardiac dysfunction: echocardiography results of the HAARLEM study. Front Reprod Health. 2021;3:732318. doi:10.3389/frph.2021.732318. PMID 36304014.Abdullah R, Bjørnebekk A, Hauger LE, Hullstein IR, Edvardsen T, Haugaa KH, Almaas VM. Severe biventricular cardiomyopathy in both current and former long-term users of anabolic-androgenic steroids. Eur J Prev Cardiol. 2024;31(5):599-608. doi:10.1093/eurjpc/zwad362. PMID 37992194.Keogh JWL, Winwood PW. The epidemiology of injuries across the weight-training sports. Sports Med. 2017;47(3):479-501. doi:10.1007/s40279-016-0575-0. PMID 27328853.Aasa U, Svartholm I, Andersson F, Berglund L. Injuries among weightlifters and powerlifters: a systematic review. Br J Sports Med. 2017;51(4):211-219. doi:10.1136/bjsports-2016-096037. PMID 27707741.Page RL, Husain S, White LY, et al. Cardiac arrest at exercise facilities: implications for placement of automated external defibrillators. J Am Coll Cardiol. 2013;62(22):2102-2109. doi:10.1016/j.jacc.2013.06.048. PMID 23933539.Hollings M, Mavros Y, Freeston J, Fiatarone Singh M. The effect of progressive resistance training on aerobic fitness and strength in adults with coronary heart disease: a systematic review and meta-analysis of randomised controlled trials. Eur J Prev Cardiol. 2017;24(12):1242-1259. doi:10.1177/2047487317713329.Momma H, Kawakami R, Honda T, Sawada SS. Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies. Br J Sports Med. 2022;56(13):755-763. doi:10.1136/bjsports-2021-105061. PMID 35228201.O'Keefe JH, O'Keefe EL, Eckert R, Lavie CJ. Training strategies to optimize cardiovascular durability and life expectancy. Mo Med. 2023;120(2):155-162. PMID 37091937. PMCID PMC10121111.Currier BS, McLeod JC, Banfield L, et al. American College of Sports Medicine position stand: resistance training prescription for muscle function, hypertrophy, and physical performance in healthy adults: an overview of reviews. Med Sci Sports Exerc. 2026;58(4):851-872. PMID 41843416.Ralston GW, Kilgore L, Wyatt FB, Buchan D, Baker JS. Weekly training frequency effects on strength gain: a meta-analysis. Sports Med Open. 2018;4(1):36. doi:10.1186/s40798-018-0149-9. PMID 30076500.Pelland JC, Remmert JF, Robinson ZP, Hinson SR, Zourdos MC. The resistance training dose response: meta-regressions exploring the effects of weekly volume and frequency on muscle hypertrophy and strength gains. Sports Med. 2026;56(2):481-505. doi:10.1007/s40279-025-02344-w. PMID 41343037.Ortega FB, Silventoinen K, Tynelius P, Rasmussen F. Muscular strength in male adolescents and premature death: cohort study of one million participants. BMJ. 2012;345:e7279. doi:10.1136/bmj.e7279. PMID 23144234.Ruiz JR, Sui X, Lobelo F, et al. Association between muscular strength and mortality in men: prospective cohort study. BMJ. 2008;337:a439. doi:10.1136/bmj.a439. PMID 18595904.Timpka S, Petersson IF, Zhou C, Englund M. Muscle strength in adolescent men and risk of cardiovascular disease events and mortality in middle age. BMC Med. 2014;12:62. doi:10.1186/1741-7015-12-62. PMID 24731728.Leong DP, Teo KK, Rangarajan S, et al. Prognostic value of grip strength: findings from the Prospective Urban Rural Epidemiology (PURE) study. Lancet. 2015;386(9990):266-273. doi:10.1016/S0140-6736(14)62000-6. PMID 25982160.Tieland M, Verdijk LB, de Groot LCPGM, van Loon LJC. Handgrip strength does not represent an appropriate measure to evaluate changes in muscle strength during an exercise intervention program in frail older people. Int J Sport Nutr Exerc Metab. 2015;25(1):27-36. doi:10.1123/ijsnem.2013-0123. PMID 24903908.Grgic J, Garofolini A, Orazem J, Sabol F, Schoenfeld BJ, Pedisic Z. Effects of resistance training on muscle size and strength in very elderly adults: a systematic review and meta-analysis of randomized controlled trials. Sports Med. 2020;50(11):1983-1999. doi:10.1007/s40279-020-01331-7. PMID 32740889.Huebner M, Riemann B, Hatchett A. Grip strength and sports performance in competitive master weightlifters. Int J Environ Res Public Health. 2023;20(3):2033. doi:10.3390/ijerph20032033. PMID 36767396.López-Bueno R, Andersen LL, Koyanagi A, et al. Thresholds of handgrip strength for all-cause, cancer, and cardiovascular mortality: a systematic review with dose-response meta-analysis. Ageing Res Rev. 2022;82:101778. doi:10.1016/j.arr.2022.101778.MacDonald HV, Johnson BT, Huedo-Medina TB, et al. Dynamic resistance training as stand-alone antihypertensive lifestyle therapy: a meta-analysis. J Am Heart Assoc. 2016;5(10):e003231. doi:10.1161/JAHA.116.003231. PMID 27680663.Bhasin S, Travison TG, Manini TM, et al. Sarcopenia definition: the position statements of the Sarcopenia Definition and Outcomes Consortium. J Am Geriatr Soc. 2020;68(7):1410-1418. doi:10.1111/jgs.16372. PMID 32150289.Cawthon PM, Manini T, Patel SM, et al.

Nearly every warning you've heard about lifting weights was written down before anybody checked it. We trace where those warnings came from, starting with a Harvard student in 1854 and ending with a curve on a graph that's being used today to argue you can lift too much.Along the way: the men who built themselves with barbells and then sold the public five-pound dumbbells, because iron was expensive to mail and a booklet cost pennies. The muscle-bound myth, which nobody could define when a graduate student surveyed 45 physiologists about it. The 1961 report that took the deep squat out of every branch of the American military, measured with a device its author built himself and never validated. The claim that lifting stunts a child's growth, which no professional body ever actually made. And the argument women got, which was never about injury at all.Timestamps:0:00 Intro2:33 2,500 years of people picking up heavy things7:24 George Windship and the Health Lift10:56 Blaikie's truck horse and the muscle-bound myth14:59 Bernarr Macfadden19:39 Charles Atlas and Dynamic Tension27:01 Carl Klein, a homemade device, and the parallel squat30:57 Thomas Delorme and three sets of ten35:20 Kids, growth plates, and where the stunting idea came from41:43 Women, "you'll get bulky," and Dudley Sargent in 191250:05 Pregnancy, from 1949 to a 2025 barbell study53:40 The pattern, and the curve on next week's graphResources:Buy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/New Barbell Medicine Hybrid 5K and 10K Run + Lift ProgramsBarbell Medicine coaching and templates: https://www.barbellmedicine.com1. Downs DS, Chasan-Taber L, Evenson KR, Leiferman J, Yeo S. Physical activity and pregnancy: past and present evidence and future recommendations. Res Q Exerc Sport. 2012;83(4):485-502. doi:10.1080/02701367.2012.10599138. PMID 23367811.2. McMurray RG, Mottola MF, Wolfe LA, Artal R, Millar L, Pivarnik JM. Recent advances in understanding maternal and fetal responses to exercise. Med Sci Sports Exerc. 1993;25(12):1305-1321. PMID 8107536.3. Smith KM, Campbell CG. Physical activity during pregnancy: impact of applying different physical activity guidelines. J Pregnancy. 2013;2013:165617. doi:10.1155/2013/165617. PMID 23476778.4. American College of Obstetricians and Gynecologists. Physical activity and exercise during pregnancy and the postpartum period. ACOG Committee Opinion No. 804. Obstet Gynecol. 2020;135(4):e178-e188. doi:10.1097/AOG.0000000000003772. PMID 32217980.5. American Academy of Pediatrics Committee on Sports Medicine and Fitness. Strength training by children and adolescents. Pediatrics. 2001;107(6):1470-1472. doi:10.1542/peds.107.6.1470. PMID 11389279.6. Stricker PR, Faigenbaum AD, McCambridge TM; Council on Sports Medicine and Fitness. Resistance training for children and adolescents. Pediatrics. 2020;145(6):e20201011. doi:10.1542/peds.2020-1011. PMID 32457216.7. Gardiner EN. Athletics of the Ancient World. Clarendon Press; 1930:54. See also Gardiner EN. Olympia: Its History and Remains. Clarendon Press; 1925.8. Heffernan C. The Bybon stone and ancient strength. Physical Culture Study. 2021. Accessed September 2026. https://physicalculturestudy.com.9. Pausanias. Description of Greece. 6.14.5. Jones WHS, trans. Loeb Classical Library. Harvard University Press.10. Quintilian. Institutio Oratoria. 1.9.5. Butler HE, trans. Loeb Classical Library. Harvard University Press.11. Heffernan C. Milo of Croton and the invention of progressive overload. Physical Culture Study. 2026. Accessed September 2026. https://physicalculturestudy.com. See also H.J. Lutcher Stark Center for Physical Culture and Sports, University of Texas at Austin, Milo Bar-Bell Company holdings.12. Liddell HG, Scott R. A Greek-English Lexicon. 9th ed. Clarendon Press; entry γυμνάσιον. Thucydides. History of the Peloponnesian War. 1.6. Crawley R, trans.13. Tomlinson RA. Gymnasium. In: Oxford Classical Dictionary. Oxford University Press; 2015. doi:10.1093/acrefore/9780199381135.013.2963. See also Stavrou D. The Greek Gymnasium [thesis]. University of Leicester; 2016:38.14. Xenophon. Constitution of the Lacedaimonians. 1.4. Marchant EC, trans. Loeb Classical Library. Harvard University Press.15. Plutarch. Life of Lycurgus. 14. Perrin B, trans. Loeb Classical Library. Harvard University Press.16. Ollier F. Le Mirage Spartiate. Vols 1-2. Boccard; 1933-1943. Discussed in Rahe PA. The Grand Strategy of Classical Sparta. Yale University Press; 2016. See also Christesen P. Utopia on the Eurotas: Economic Aspects of the Spartan Mirage. In: Powell A, Hodkinson S, eds. Sparta: The Body Politic. Classical Press of Wales; 2010.17. Pausanias. Description of Greece. 5.16. Jones WHS, trans. Loeb Classical Library. Harvard University Press.18. Scarborough J. Galen and the gladiators. Episteme. 1971;5:98-111.19. Tipton CM. The history of "Exercise Is Medicine" in ancient civilizations. Adv Physiol Educ. 2014;38(2):109-117. doi:10.1152/advan.00136.2013. PMCID PMC4056176.20. Vegetius FR. De Re Militari (The Military Institutions of the Romans). Book I. Clarke J, trans. 1767.21. Surviving halteres: a catalogue. EXARC Journal. 2017;(3). Accessed September 2026. https://exarc.net.22. Talaga M. Physical culture in the Middle Ages: revisiting the disappearance thesis. Cogent Arts Humanit. 2025. doi:10.1080/23311983.2025.2482388.23. Rawcliffe C. Health and the environment in the medieval hospital. History. 2022. doi:10.1111/1468-229X.13238.24. Elyot T. The Boke Named the Governour. 1531. Croft HHS, ed. Kegan Paul; 1883:171.25. Campillo P, Caballero D. Girolamo Mercuriale and the art of gymnastics. Hektoen International. 2020. Accessed September 2026. https://hekint.org.26. Todd T. The myth of the muscle-bound lifter. NSCA J. 1985;7(3):37-41. Citing Van Doren C. Benjamin Franklin. Viking Press; 1938.27. Galen. Exhortation to the Study of the Arts (Protrepticus). Chapters 9-14. Walsh J, trans. Medical Life. 1930;37:507-529. See also Xenophontos S. Galen's Exhortation to the Study of Medicine. In: Bouras-Vallianatos P, Xenophontos S, eds. Greek Medical Literature and Its Readers. Routledge; 2018:67-93.28. Todd J. "Strength is Health": George Barker Windship and the first American weight training boom. Iron Game History. 1993;3(1):3-14. https://starkcenter.org/igh/igh-v3/igh-v3-n1/igh0301c.pdf.29. Windship GB. Autobiographical sketches of a strength-seeker. Atlantic Monthly. 1862;9(51):102-115.30. US Patent 46,413. Improvement in graduated dumb-bells. GB Windship, Boston. Granted 14 February 1865.31. Savage DF. US Patent 28,505. 1860.32. The Health-Lift Reduced to a Science: Cumulative Exercise, A Thorough Gymnastic System in Ten Minutes Once a Day. New York: Health-Lift Company; 1875.33. Blaikie W. How to Get Strong and How to Stay So. New York: Harper & Brothers; 1879:99-100.34. Bryant D. William Blaikie and physical fitness in late nineteenth century America. Iron Game History. 1992;2(3):3.35. Sandow E. Sandow on Physical Training. Adam GM, ed. 1894:12, 23, 207.36. Sandow E. Strength and How to Obtain It. London: Gale & Polden; 1897:34, Table 7.37. Sandow E. Strength and How to Obtain It. Revised ed. London: Gale & Polden; [c1899]. Project Gutenberg ebook 65987.38. Todd J, Todd T. Requiem for a strongman: reassessing the career of Professor Louis Attila. Iron Game History. 2002;7(2-3):42-55.39. Pall Mall Gazette. December 1889. Clipping in Attila's scrapbook, Todd-McLean Collection, H.J. Lutcher Stark Center, University of Texas at Austin.40. Chapman D. Sandow's first triumph. Iron Game History. 1994;3(3):3-8.41. Robert Hoffman Business Papers finding aid. H.J. Lutcher Stark Center for Physical Culture and Sports, University of Texas at Austin.42. Hall DT, Fair JD. The pioneers of protein. Iron Game History. 2004;8(3):26-28.43. Shurley J, Todd J. Joe Weider, All American Athlete, and the promotion of strength training for sport: 1940-1969. Iron Game History. 2012;12(1):9-12.44. Todd J. Bernarr Macfadden: reformer of feminine form. Iron Game History. 1991;1(4-5):3-8.45. Yagoda B. The true story of Bernarr Macfadden. American Heritage. 1981;33(1):22-28.46. Murtha R, Heffernan C, Hunt T. Building American supermen? Bernarr MacFadden, Benito Mussolini and American fascism in the 1930s. Sport in Society. 2020. doi:10.1080/17430437.2020.1865313.47. New York Times. 6 October 1905:10; 10 October 1905:9.48. Macfadden B. Macfadden's Encyclopedia of Physical Culture. New York: Physical Culture Publishing; 1912:847. Quoted in Todd T, NSCA J. 1985;7(3):37-41.49. Danna S. Charles Atlas: muscle man. Iron Game History. 1996;4(4):3-6, 12-14. https://starkcenter.org/igh/igh-v4/igh-v4-n4/igh0404c.pdf.50. Guide to the Charles Atlas Records, NMAH.AC.0654. Archives Center, National Museum of American History, Smithsonian Institution.51. Charles Atlas course text, undated later edition.52. Charles P. Roman: a gloriously healthy life. Chief Marketer.53. Kannenberg G Jr. The ad that made an icon out of Mac. Hogan's Alley. 1999;2(3).54. Michigan State University Libraries comic art index, Charles Atlas advertisements. https://comics.lib.msu.edu/rri/arri/atlas.htm.55. Charles Atlas. Encyclopedia.com.56. Todd J, Todd T. The conversion of Dr. Peter Karpovich. Iron Game History. 2005;8(4):4-12. https://starkcenter.org/igh/igh-v8/igh-v8-n4/igh0804c.pdf.57. Murray J, Karpovich P. Weight Training in Athletics. Englewood Cliffs, NJ: Prentice-Hall; 1956.58. Murray J. John Carrol Grimek: the nonpareil. Iron Game History. 1994;3(3):10-12.59. Zorbas WS, Karpovich PV. The effect of weight lifting upon the speed of muscular contractions. Res Q. 1951;22(2):145-148.60. Klein KK. The deep squat exercise as utilized in weight training for athletes and its effect on the ligaments of the knee. J Assoc Phys Ment Rehabil. 1961;15(1):6-11, 23.61. Sports Illustrated. Coverage of Klein's knee-ligament findings. 1962.62. Todd T. Karl Klein and the squat. NSCA J. 1984;6(3):26-31.63. Chandler TJ, Wilson GD, Stone