Cold wraps were placed on both legs for 20 minutes. Heat wraps were left on subjects' legs for eight hours to give adequate time for the heat to penetrate deeply into muscle. (The temperature -- about 104 degrees Fahrenheit -- was low enough so as not to burn the skin.) The verdict: Both heat and cold therapy reduced soreness, but cold -- whether applied immediately after exercise or 24 hours later -- was superior to heat.
Though scientists aren't sure exactly why cold or heat might reduce DOMS, it is known that the two have opposite physiological effects: Cold constricts blood vessels and reduces blood flow, while heat dilates vessels and increases flow. Based on this, some athletes alternate between cold and heat, which they claim creates a "pumping action" of constriction and dilation that removes waste products from muscles and brings in fresh blood. Known as contrast therapy, this approach typically involves spending one or two minutes in a cold bath followed by a warm bath, and then repeating the sequence multiple times.
Pooling data from 13 studies, researchers found that contrast therapy decreases post-exercise soreness more than resting does. But it doesn't appear to offer any advantages over cold water alone. While it's possible that longer times in the water might yield different results, all the tub hopping probably isn't worth the effort.
Getting a massage is certainly more enjoyable than sitting in a cold bath, and research suggests it may reduce DOMS, at least temporarily. In a review of nine studies on massage, six of them found that it alleviated soreness. The rub, however, is that the benefit generally occurred only in the early stages of DOMS, at 24 hours post-exercise. At 48 and 72 hours after exercise, there was less evidence that massage helped.
Though researchers aren't sure why massage reduces pain, possible explanations include its effects on inflammation, stress hormones or the nervous system. Another theory is that massage increases blood flow to muscles, though some studies refute this idea and even show that massage may have the opposite effect. Perhaps the most common explanation is that it works by removing lactic acid. But as previously mentioned, lactic acid isn't a cause of DOMS.
Because studies have used different massage techniques, it's unclear which methods are most effective. There's also uncertainty about timing and duration, though in most of the studies that showed a benefit, massages were done two or three hours after exercise and lasted 20 to 30 minutes.
One possible downside of massage is the cost. But self-massage performed with a foam roller may be a relatively inexpensive alternative.
Tart cherry juice
Though the research is preliminary, there is some evidence that tart cherry juice can reduce soreness. For example, in a small, randomized study, male college students drank either tart cherry juice or a placebo beverage for four days, did bicep curls to induce DOMS, and then drank their assigned beverage for another four days. Those consuming the cherry juice reported less soreness than the non juice-drinkers, and their pain peaked and declined more rapidly.