Do cold-water plunges really speed post-workout muscle recovery?

Post-workout cold plunges may be having a moment, but a new study dunks on the practice. After a tough workout, muscle recovery was no better in women who immersed themselves in chilly water than in women who didn’t. No recovery benefits came from a hot soak, either. The decidedly tepid results appear May 7 in PLOS One.

Thirty women completed five sets of 20 drop-jumps — grueling exercises that require a drop from a thigh-high box followed immediately by a powerful jump on the ground. Afterward, the exercisers, whose average age was 23, followed one of three recovery protocols: a 10-minute dip in 10° Celsius water, a 10-minute dip in 40° C water or nothing. Two hours after the first soak, the participants did another one. One, two and three days after the experiment, researchers looked for signs of muscle recovery, including muscle strength, soreness and swelling. They also measured creatine kinase, a marker of muscle damage in the blood.