Barbell Medicine Podcast

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 plunges
19:44 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 4
1:56 Mouth tape, Zone 2, and saunas 
47:44 What actually works
Resources

Buy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/
Free Vital 5 Action Plan
New Barbell Medicine Hybrid 5K and 10K Run + Lift Programs
Barbell Medicine coaching and templates: https://www.barbellmedicine.com
Get 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/
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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.

Timestamps
00:00 The jogging J-curve and the headlines
02:42 The Danish study, its confidence interval, and what a MET measures
08:02 Better measurement: 15 check-ins and fitness on a treadmill
12:51 Atrial fibrillation: the dose, the mechanism, and stroke risk
22:06 Coronary calcium and heart scarring in masters athletes
25:58 The marathon death story and cardiac arrest rates
29:08 How much training it takes to keep getting fitter
34:12 Does cardio interfere with your lifting gains
39:52 Flux, the athlete's paradox, and liver fat
44:12 Cardio, weight loss, and metabolic compensation
51:13 Bone density in cyclists and energy availability
57:51 Writing the cardio guidelines

Resources
Buy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/

Free Vital 5 Action Plan

New Barbell Medicine Hybrid 5K and 10K Run + Lift Programs

Barbell Medicine coaching and templates: https://www.barbellmedicine.com

Get early access, ad-free listening, and exclusive content here: https://barbellmedicine.supercast.com/

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25. 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.70025
26. 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/JP273480
27. 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-y
28. 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.2015.02.022
29. 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.2022-0043
30. 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/M14-1189
31. 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.2026.01.025
33. 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.0b013e3181c6a116
35. 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:10.1186/1741-7015-10-168
36. 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.2016.02.013
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40. Kim JH, Malhotra R, Chiampas G, et al. Cardiac arrest during long-distance running races. N Engl J Med. 2012. doi:10.1056/NEJMoa1106468
41. Areta JL, Meehan E, Howe G, Redman LM. Energetics of a world-tour female road cyclist during a multistage race (Tour de France Femmes). Int J Sport Nutr Exerc Metab. 2024;34(5):253-257. doi:10.1123/ijsnem.2023-0275
42. Saris WH, van Erp-Baart MA, Brouns F, Westerterp KR, ten Hoor F. Study on food intake and energy expenditure during extreme sustained exercise: the Tour de France. Int J Sports Med. 1989;10(suppl 1):S26-S31.

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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 them

Resources
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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.
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Koopman R, Manders RJF, Jonkers RAM, Hul GBJ, Kuipers H, van Loon LJC. Intramyocellular lipid and glycogen content are reduced following resistance exercise in untrained healthy males. Eur J Appl Physiol. 2006;96(5):525-534. doi:10.1007/s00421-006-0139-3. PMID 16369816.
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US Department of Health and Human Services. Physical Activity Guidelines for Americans. 2nd ed. USDHHS; 2018.

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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 Intro
2:33 2,500 years of people picking up heavy things
7:24 George Windship and the Health Lift
10:56 Blaikie's truck horse and the muscle-bound myth
14:59 Bernarr Macfadden
19:39 Charles Atlas and Dynamic Tension
27:01 Carl Klein, a homemade device, and the parallel squat
30:57 Thomas Delorme and three sets of ten
35:20 Kids, growth plates, and where the stunting idea came from
41:43 Women, "you'll get bulky," and Dudley Sargent in 1912
50:05 Pregnancy, from 1949 to a 2025 barbell study
53:40 The pattern, and the curve on next week's graph

Resources:
Buy the book, Signal: https://www.barbellmedicine.com/shop/learning/signal/

New Barbell Medicine Hybrid 5K and 10K Run + Lift Programs

Barbell Medicine coaching and templates: https://www.barbellmedicine.com

1. 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.

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Parts of the country now get a few weeks of wildfire smoke every year, and the obvious question is whether there is a point where the air is bad enough that the workout costs you more than it gives you. We went and looked. There is a real number, it comes from about 1.5 million people, and it is not the number that gets quoted.
This is a free preview of Direct Line, our monthly ask-us-anything for Barbell Medicine Plus subscribers. Two of this month's twelve questions are here in full.
First: training in wildfire smoke. What PM2.5 is, why the AQI on your phone and the number in the paper are not the same quantity, where the 90-minutes-at-100-micrograms figure comes from and why it is softer than it sounds, what happened when six cities modeled telling people to stay inside, and why your breathing rate during a set of squats matters more than you would think.
Second: the effective reps model. A subscriber noticed that if a set only counts when you are within five reps of failure, the triceps in a heavy bench press should not count, and if you are going to count that as a fractional set for the triceps, then a warm-up set counts for the chest. Both cannot be true. We go through the meta-regression on proximity to failure, the 67-study analysis that tested whether an indirect set should count as one, as half, or as zero, and where we actually put our sets.

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Timestamps
1:47 The question: is there a point where the air is too bad to train?
2:37 What PM2.5 actually is
3:05 AQI vs micrograms, and why your phone disagrees with the paper
3:50 Where the "90 minutes" number comes from
4:54 Austin: what breathing this air does to your lungs
9:14 1.5 million adults: does dirty air cancel the benefit of exercise?
10:44 Six cities modeled staying indoors. Mortality did not improve.
11:22 Lifting vs cycling: breathing rate is the whole mechanism
12:33 Indoor air during a wildfire, and what filtration does not fix
13:24 Is wildfire smoke worse than city pollution?
14:38 What we would actually tell a patient
18:35 The question: hard sets, fractional sets, and the five-rep rule
19:18 Reps in reserve, hard sets, and fractional sets defined
20:19 The meta-regression: no threshold, just a line
21:13 Do indirect sets count as half a set?
23:08 Would you rather: every set at 5 RIR, or every set to failure?
25:22 Why you get worse at judging RIR the further you are from failure
28:42 The numbers we use: RPE 7 to 9 for hypertrophy, 4 to 6 for strength
29:20 Austin: individual variation dwarfs all of this
33:28 Why nobody can measure training load in the weight room

Resources
Tainio M, de Nazelle AJ, Götschi T, et al. Can air pollution negate the health benefits of cycling and walking? Prev Med. 2016;87:233-236. doi:10.1016/j.ypmed.2016.02.002. PMID 27156248
Ku PW, Steptoe A, Hamer M, et al. Does ambient PM2.5 reduce the protective association of leisure-time physical activity with mortality? A systematic review, meta-analysis, and individual-level pooled analysis of cohort studies involving 1.5 million adults. BMC Med. 2025;23(1):647. doi:10.1186/s12916-025-04496-y. PMID 41310726
Giallouros G, Kouis P, Papatheodorou SI, Woodcock J, Tainio M. The long-term impact of restricting cycling and walking during high air pollution days on all-cause mortality: health impact assessment study. Environ Int. 2020;140:105679. doi:10.1016/j.envint.2020.105679. PMID 32353667
Sun S, Cao W, Qiu H, et al. Benefits of physical activity not affected by air pollution: a prospective cohort study. Int J Epidemiol. 2020;49(1):142-152. doi:10.1093/ije/dyz184. PMID 31504557
Robles P, Araujo T, Brooks D, et al. Cardiorespiratory responses to short bouts of resistance training exercises in individuals with chronic obstructive pulmonary disease: a comparison of exercise intensities. J Cardiopulm Rehabil Prev. 2017;37(5):356-362. doi:10.1097/HCR.0000000000000282. PMID 28858033
Liang Y, Sengupta D, Campmier MJ, Lunderberg DM, Apte JS, Goldstein AH. Wildfire smoke impacts on indoor air quality assessed using crowdsourced data in California. Proc Natl Acad Sci U S A. 2021;118(36):e2106478118. doi:10.1073/pnas.2106478118. PMID 34465624
Aguilera R, Corringham T, Gershunov A, Benmarhnia T. Wildfire smoke impacts respiratory health more than fine particles from other sources: observational evidence from Southern California. Nat Commun. 2021;12(1):1493. doi:10.1038/s41467-021-21708-0. PMID 33674571
US Environmental Protection Agency. Air Quality Index (AQI) breakpoints. Air Quality System code tables. Accessed August 10, 2026. https://aqs.epa.gov/aqsweb/documents/codetables/aqi_breakpoints.html
Robinson ZP, Pelland JC, Remmert JF, Refalo MC, Jukic I, Steele J, et al. Exploring the dose-response relationship between estimated resistance training proximity to failure, strength gain, and muscle hypertrophy: a series of meta-regressions. Sports Med. 2024;54(9):2209-2231. doi:10.1007/s40279-024-02069-2. PMID 38970765
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

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