Should you ice bath after hard cardio?
Does a Cold Plunge After HIIT Kill Your Gains? A 5-Week Trial Checked the Muscle
· By Anthony Falcone
Verdict: Keep it, with a caveat. After interval training, a regular cold plunge neither helped nor hurt fitness gains. So use it if it makes you feel better, but don't expect it to make you fitter, and keep it away from your lifting sessions.
What the researchers tested
Sixteen healthy men did the same interval programme: three sessions a week of five to eight 2-minute runs at 95% of the speed that maxes out their oxygen uptake.
After every session, nine of them sat waist-deep in water at about 11 °C; the other seven sat at room temperature. Researchers took muscle biopsies and ran fitness tests at the start, after four weeks and after five weeks.
What they found
Training worked for everyone: VO2max, time to exhaustion, satellite cells (the muscle's repair cells) and PGC-1α (a marker of new mitochondria) all went up over time.
The ice bath changed none of it. No difference between groups in fitness, performance, muscle markers or muscle inflammation.
The authors' conclusion is blunt: routine cold-water immersion after training can't be recommended to boost adaptation, because it adds nothing. They also note it remains a reasonable tool for short-term relief, like soreness.
The part that matters for lifters
The authors point out that earlier studies found a different picture after resistance training: there, regular cold plunges have been linked to smaller strength and muscle gains. This trial only looked at interval running, so it doesn't change that advice.
What this means for you
- After cardio or HIIT, a cold plunge is optional. It won't make you fitter, and it didn't make anyone less fit here.
- After lifting, keep cold water away from the session if muscle growth is the goal.
- If you like cold exposure for mood or alertness, take it on a rest day or several hours away from strength work.
How much to trust it
- Very small study: 16 men, all young and untrained. No women.
- There was no placebo version of an ice bath, and body temperature wasn't measured.
- Five weeks is short. Longer programmes could behave differently.
The study
Malta ES, Neto JCR, Beck WR, Cornachione AS, et al. Regular Cold-Water Immersion Following HIIT Does Not Affect Intramuscular Adaptation Markers, Inflammatory Profile or Endurance Performance. Scandinavian Journal of Medicine & Science in Sports, 2026. doi.org/10.1111/sms.70241
Our Cold & Heat Exposure Protocol covers when to use cold versus heat, how to progress cold exposure safely, and how to time it around training. See the protocol