Cold plunges are one of the biggest fitness trends right now. Tubs of ice water show up on every feed, often right after a heavy lifting session. If your goal is to build muscle, that timing is the problem. A growing set of studies shows that a regular ice bath right after strength training can shrink the gains you're training for.
This post covers what the research found, why it happens, and when cold water can still be useful.
Please read first. This post is general information, not medical advice. Sudden cold water triggers a gasp and a fast jump in heart rate and blood pressure, known as cold shock, and it can disturb heart rhythm (Tipton et al., 2017). If you have a heart condition, high blood pressure, Raynaud's or any medical condition, or you're pregnant, talk to your doctor before trying cold water immersion. Never plunge alone or after drinking alcohol. If you feel chest pain, faint, or can't stop shivering once you're out and warm, get medical care.
What studies found on ice baths and muscle
The study that started it
In a 2015 study in The Journal of Physiology, 21 physically active men did 12 weeks of strength training, 2 days a week (Roberts et al., 2015). After every session, half of them sat in 10°C water up to the waist for 10 minutes. The other half did 10 minutes of easy cycling instead.
- Strength and muscle mass increased more in the easy cycling group.
- In the cycling group, type II muscle fibres (the ones that grow most with lifting) got 17% bigger, and the number of nuclei in each fibre rose 26%. Neither changed significantly in the cold water group.
- Muscle biopsies showed why. After a single workout, cold water dampened the activity of satellite cells, which help muscle repair and grow, and of a key signal for muscle growth.
The authors' conclusion was direct: using cold water immersion as a regular recovery habit "should be reconsidered."
More studies, same direction
- Cold water cuts muscle building after a workout. In a 2020 study, 12 men did leg workouts with one leg in 8°C water for 20 minutes afterward and the other leg in warm water. Over 2 weeks, muscle protein synthesis, the process that builds new muscle, was lower in the cold leg (1.48% vs 1.67% a day) (Fuchs et al., 2020).
- Smaller muscle fibre growth, even when strength kept up. In a 2019 study, men did whole body strength training 3 days a week for 7 weeks, followed by 15 minutes in 10°C water or rest at room temperature. Fibre growth was blunted in the cold group, but leg press strength improved about the same in both (Fyfe et al., 2019).
- The pooled evidence leans against cold water after lifting. A 2021 meta analysis of 8 studies found that regular cold water immersion during strength training led to smaller gains in maximal strength, strength endurance and power, with a moderate effect size (standardized mean difference about 0.6) (Malta et al., 2021). The same review found no clear effect on endurance training results.
So "ruining your gains" overstates it. The effect in most studies is a smaller gain, not a loss, and some studies found strength still improved. But if you're putting in the work to build muscle, ice baths after every session can make that work pay off less.
Ice bath vs no ice bath after lifting
Results from two studies. Switch views to compare.
Why does cold get in the way?
Lifting causes a short burst of inflammation and growth signalling in the muscle that starts the repair and building process. Reviews of this research suggest cold water dampens that response, with lower activation of growth pathways and lower muscle protein synthesis after training (Petersen and Fyfe, 2021). The evidence on the exact mechanism is still limited, and the authors note methods vary a lot between studies.
Where cold water still has a place
Cold water isn't useless. It just does a different job.
- It can ease soreness. A meta analysis of 36 studies found that cooling, especially cold water immersion, reduced muscle soreness at 24, 48 and 96 hours after hard exercise, though it didn't change any objective blood marker of recovery (Hohenauer et al., 2015).
- It can help when you need to recover fast. If you play a sport with games or races close together, the short term recovery may be worth more than the long term gain. A 2026 review put it simply: use cold water when fast recovery between sessions matters most, and skip it after strength training when muscle growth is the main goal (Tornero-Aguilera et al., 2026).
- Endurance training seems less affected. The 2021 meta analysis found no clear effect of regular cold water on endurance results (Malta et al., 2021).
Whether a cold plunge earlier in the day or on a rest day affects muscle growth hasn't been well studied, so we can't tell you it's safe for your gains either way.
What to do instead after a lifting session
- Cool down with easy movement. In the 2015 study, 10 minutes of easy cycling was the recovery that came with the better results (Roberts et al., 2015).
- Eat protein after you train. Our post on protein for muscle growth covers how much you need.
- Sleep. Our post on sleep and recovery explains why it matters for muscle.
- Train with a plan. Gains come from lifting with progressive load, enough volume and good technique, week after week.
- If you love the cold, move it. Save it for days you aren't trying to build muscle, or for times when quick recovery matters more.
Should I take an ice bath today?
Pick what you just did and what you want most right now.
What did you just do?
What matters most?
General guidance from the studies in this post, not medical advice. Check with your doctor first if you have a heart condition or high blood pressure. Sources: Roberts 2015; Malta 2021; Hohenauer 2015; Tornero-Aguilera 2026.
How we can help
At Inner G, a fitness studio in Concord, our coaches run small group strength, conditioning, mobility, yoga and breathwork classes, capped at 16 people, so a coach can teach you the lifts, watch your form and progress your training. If muscle is your main goal, one on one personal training gives you a plan designed around how you train, recover and eat, with a coach adjusting it as you get stronger.
We don't offer cold plunges or ice baths at the studio, and we're coaches, not doctors.
- Try 7 days of unlimited classes for $30. Join by day 5 and your $30 is credited toward your membership. Book your class.
- Want a plan of your own? See personal training in Vaughan.
- Want help with food? See nutrition coaching in Vaughan.
Questions? Call (289) 536-8066 or email g-squad@innerg.ca.
References
Fuchs CJ, Kouw IWK, Churchward-Venne TA, Smeets JSJ, Senden JM, van Marken Lichtenbelt WD, Verdijk LB, van Loon LJC. (2020). Postexercise cooling impairs muscle protein synthesis rates in recreational athletes. The Journal of Physiology, 598(4):755-772. doi:10.1113/JP278996. PubMed · PMC
Fyfe JJ, Broatch JR, Trewin AJ, Hanson ED, Argus CK, Garnham AP, Halson SL, Polman RC, Bishop DJ, Petersen AC. (2019). Cold water immersion attenuates anabolic signaling and skeletal muscle fiber hypertrophy, but not strength gain, following whole-body resistance training. Journal of Applied Physiology, 127(5):1403-1418. doi:10.1152/japplphysiol.00127.2019. PubMed
Hohenauer E, Taeymans J, Baeyens JP, Clarys P, Clijsen R. (2015). The effect of post-exercise cryotherapy on recovery characteristics: a systematic review and meta-analysis. PLoS One, 10(9):e0139028. doi:10.1371/journal.pone.0139028. PubMed · PMC
Malta ES, Dutra YM, Broatch JR, Bishop DJ, Zagatto AM. (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. doi:10.1007/s40279-020-01362-0. PubMed
Petersen AC, Fyfe JJ. (2021). Post-exercise cold water immersion effects on physiological adaptations to resistance training and the underlying mechanisms in skeletal muscle: a narrative review. Frontiers in Sports and Active Living, 3:660291. doi:10.3389/fspor.2021.660291. PubMed · PMC
Roberts LA, Raastad T, Markworth JF, Figueiredo VC, Egner IM, Shield A, Cameron-Smith D, Coombes JS, Peake JM. (2015). Post-exercise cold water immersion attenuates acute anabolic signalling and long-term adaptations in muscle to strength training. The Journal of Physiology, 593(18):4285-4301. doi:10.1113/JP270570. PubMed · PMC
Tipton MJ, Collier N, Massey H, Corbett J, Harper M. (2017). Cold water immersion: kill or cure? Experimental Physiology, 102(11):1335-1355. doi:10.1113/EP086283. PubMed
Tornero-Aguilera JF, Lozano-Meca J, López-Moreno M, Sancho-Haro ES, Muñoz-López M, Baz-Valle E, López-Gil JF, Yáñez-Sepúlveda R, Clemente-Suárez VJ. (2026). The cold-water immersion recovery-adaptation paradox: reconciling acute parasympathetic and analgesic benefits with chronic hypertrophy attenuation. Experimental Physiology, online ahead of print. doi:10.1113/EP094042. PubMed · PMC
Want a coach to do this with you? See personal training in Vaughan or small group fitness classes.