Slipping into a cold-water bath for 20 minutes after exercise may seem more like punishment than relief for aching muscles, but many athletes and bodybuilders have relied on cold-water therapy as a way to get relief for sore muscles after workouts. Now, researchers are questioning whether cold water baths make your muscles feel better than other treatments, such as compression stockings or stretching.
A cold-water bath—also known as cryotherapy—involves sitting in a tub of cold water for five to more than 20 minutes. In the 17 studies looked at, the water temperature ranged from 50-59°F—similar to the ocean off the coast of Nova Scotia. Most treatments involved sitting in the water for the entire time, but in some studies the participants stepped into and out of the water several times.
The researchers did find that cold-water baths were better than resting or doing nothing, reducing muscle soreness by about 20%. However, it purely eased the feeling of soreness—it didn’t make the muscles stronger. "It is important to consider that cold water immersion induces a degree of shock on the body,” lead researcher Dr. Chris Bleakley of the University of Ulster said. "We need to be sure that people aren't doing anything harmful, especially if they are exposing themselves to very cold water for long periods." He added, "Most of these studies are done in pretty elite athletes. So, their physiological reserves are probably greater than most people. I think you have to be careful that you don't generalize these conditions to everyone."
Cold-water baths should be avoided if you have a heart condition or a problem with circulation (such as Reynaud’s). Also, the quality of water should be considered. No one really wants to sit in a tub of water after 15 other sweaty guys with cuts and scrapes on their legs.