What you've heard
An ice bath after lifting helps you recover
Verdict
Wrong if building muscle is the goal
Does an ice bath after lifting help recovery?
Wrong if building muscle is the goal.
For strength training, the evidence points the other way. In a three-month trial, active men lifted twice a week and then spent ten minutes either in cold water or doing light active recovery. Strength and muscle mass rose more with active recovery. The authors wrote that cold water as a regular recovery habit "should be reconsidered." Pooled analyses since agree in direction: regular cold immersion straight after lifting blunts muscle growth and, in most analyses, strength gains, while endurance gains seem unaffected. The effect is small to moderate, and clearest when only the trained limbs are cooled.20 No pooled analysis defines a safe gap, so the cautious reading is to take the plunge on days you do not lift, or hours apart (Chapter 9).
Where the book tests it
What the book recommends instead
Reach the daily protein range for your age
ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.How: for a 155-pound person, the official minimum is roughly 55 grams a day and the current US goal 85 to 110 grams. Over 65, do not drop below about 70 to 85 grams, the expert-group floor; the upper part of the US range suits active older adults. In lifting trials, more than about 110 grams stopped adding muscle. (Per pound of body weight: the minimum is a little over a third of a gram, the US goal half to three-quarters of a gram, the over-65 floor about half a gram.) A protein food at each meal, such as eggs, yogurt, fish, beans, tofu or meat, is the easy way to get there (Chapter 5 covers the rest of the plate). Why: enough protein helps training build a little more muscle, and expert panels judge that older muscle needs more.
Heat: a sauna or a hot bath, a few times a week, if you have access and enjoy it
EmergingEvidence grade: Emerging. Early, small, animal-only, or actively contested.How: about a quarter of an hour in a sauna, or a hot bath around 104°F for ten minutes or so. Taken an hour or two before bed, a warm bath or shower shortened the time people took to fall asleep in pooled studies (Chapter 8). Why: two large cohorts link regular heat with fewer heart deaths (that link is ProbableEvidence grade: Probable. Good observational evidence with a plausible mechanism, or small or few trials.; the frequency is untested), and small trials show better artery function in unfit people. Safety: no alcohol, drink water, rise slowly, and see "Safety" below.
Sources
- 20.Roberts, L.A., Raastad, T., Markworth, J.F., Figueiredo, V.C., et al. (2015). "Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training." Journal of Physiology, 593(18), 4285-4301. https://doi.org/10.1113/JP270570; Malta, E.S., Dutra, Y.M., Broatch, J.R., Bishop, D.J., and Zagatto, A.M. (2021). "The effects of regular cold-water immersion use on training-induced changes in strength and endurance performance: a systematic review with meta-analysis." Sports Medicine, 51(1), 161-174. https://doi.org/10.1007/s40279-020-01362-0; Grgic, J. (2023). "Effects of post-exercise cold-water immersion on resistance training-induced gains in muscular strength: a meta-analysis." European Journal of Sport Science, 23(3), 372-380. https://doi.org/10.1080/17461391.2022.2033851; Piñero, A., Burke, R., Augustin, F., Mohan, A., et al. (2024). "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." European Journal of Sport Science, 24(2), 177-189. https://doi.org/10.1002/ejsc.12074 (Roberts: 21 men, 12 weeks; fast-twitch fibers grew only in the active-recovery group.)
Note numbers are those of Chapter 4, Load, Strength and Bone.
This verdict is one of the "What you've heard" boxes in Chapter 4, Load, Strength and Bone, where the book tests the claims people repeat against the studies behind them.
Educational content, not medical advice. Disclaimer.