From the London Olympics to sports-themed movies, you’ve probably seen an accomplished athlete (or an actor portraying one) submerged in icy cold water after a game or an intense workout. It’s a painful process and has the potential to be hazardous to your health if not done properly, but athletes say it speeds recovery times, reduces inflammation, and eases muscle soreness and pain.
For the study, researchers recruited 20 recreationally active college-age men to run on a treadmill for 40 minutes. After the run, half of the subjects took 20-minute ice baths, standing in thigh-high ice water cooled to 40 degrees Fahrenheit.
“That’s really cold,” says lead researcher Naomi Crystal. “I had some guys close to tears.”
To gauge the effect of ice baths on soreness, strength, swelling and inflammation, researchers took the following measurements at intervals from one hour to three days:
- perceived soreness while walking down stairs
- quadriceps strength on a resistance machine
- thigh circumference
- level of inflammation (measured the concentration of an inflammation marker in blood samples)
There was no difference between the groups in terms of strength or perceived soreness. Thigh circumference didn’t change for any of the subjects. Inflammation levels trended somewhat lower in the subjects who took ice baths, but the levels varied greatly from one subject to the next.
“The study suggested that there might have been a mild reduction in inflammation, but it wasn’t conclusive,” says study co-author Dian LaRoche, UNH associate professor of kinesiology.
Considering all of the evidence, this relatively small study found no measurable benefit to taking a cold plunge after exercise.
“It doesn’t help you feel better and it doesn’t help you perform better,” says Crystal. “Ice baths are very popular as a treatment, but the research is really mixed as to whether they’re beneficial. They’re miserable. If it doesn’t work, you don’t want to waste your time.”
Still, Crystal isn’t ready – at least personally – to write off the idea of ice baths in certain situations.
“I’m not convinced that it doesn’t help at all,” she says. “Use them sparingly. Use them in tournament situations, use them with an athlete who has done something extraordinary. But for day-to-day athletes, I wouldn’t recommend them. They’re painful, and they’re time consuming.”
The bottom line: most of us won’t see any real benefit from an ice bath (unless you happen to be an elite athlete).