Hot and cold plunges after exercise are eye-openers. But what are the benefits?
Lots of health-conscious folks are running hot and cold these days. Literally. They’re wrapping up a vigorous workout with a plunge into cold water or an icy-cold shower followed by a dip in a hot tub or a few minutes in a steam bath. This regimen, called whole-body immersion, is similar to contrast therapy, the practice of treating sports injuries with alternating cold and hot temperatures.
“The theory behind contrast therapy is that alternating between hot and cold results in cycles of dilation and constriction of the arteries and capillaries to create a pumping action,” says Amie Russell, supervisor of Orlando Health’s Healthy U Fitness Center in Orlando. That pumping action within the circulatory system, Russell says, is presumed to reduce swelling, “but there really isn’t a lot of research that supports that theory.”
Despite the dearth of evidence for contrast therapy as a treatment, whole-body immersion for post-exercise recovery has caught on.
“I know a lot of people who use it,” says Michelle Ramirez, a physical therapist with Florida Hospital who works at RDV Sportsplex in Maitland. “We have a cold plunge pool and there are a lot of members who go back and forth” between the pool and the facility’s heated whirlpool.
But Ramirez, too, says there’s conflicting evidence about the benefits of alternating heat, or thermotherapy, with cold, or cryotherapy. “There’s a theory that it can change the temperature of muscle,” she says, but studies are finding that the temperature changes “are happening more on the skin.”
Typically, ice is used within the first 72 hours of an injury. Ice causes small blood vessels to constrict, reducing blood flow, pain and swelling. Heat, which is used to treat sore muscles and joint pain, causes blood vessels to dilate, increasing circulation and muscle relaxation. After 72 hours, patients can choose contrast therapy, Ramirez says.
Truly athletic individuals, those who work out at high intensity for two or more hours most days, may benefit more from whole-body immersion than recreational athletes, Russell says. “Whenever you exercise, there’s a buildup of lactic acid, which results in swelling and inflammation. Creating constriction and dilation of the blood vessels helps circulation, flushing lactic acid out of the muscle. Lymph vessels also open and close, which assists with removal of excess fluid left behind by the circulatory system.’’
More sedentary individuals produce more lactic acid during their workouts because their bodies aren’t conditioned to buffer the acid as efficiently during exercise, Russell says. “They experience more soft tissue damage, which leads to greater inflammation.”
Still, a review of the research has convinced Dr. Gitanjali Srivastava that jumping into a swimming pool after a workout is just as good as whole-body immersion. Srivastava, medical director of the Center for Obesity Medicine at Florida Hospital Celebration Health, also notes that everyone should exercise caution when going from a strenuous workout to alternating temperature extremes. Heart disease, peripheral vascular disease, diabetes, Raynaud’s disease, and chronic obstructive pulmonary disease are among the conditions that place individuals at risk for complications—and even death—from extreme temperatures.
The bottom line from Srivastava: “You have to get clearance from your doctor.”
Still wondering whether you’re up to the Ice Bucket Challenge? Millions of people worldwide have posed for videos as a bucket of ice water is dumped on their heads. So far, the viral effort has raised millions for research into Lou Gehrig’s disease.
If you’re young—or youngish—and healthy, participating is no sweat. But if you have heart disease, stick with a donation.
“It’s like a shock to your body when you have ice water being poured over you,” says Michelle Ramirez, a physical therapist with Florida Hospital. “If you have a heart condition, it can increase your chance of having an arrhythmia, or abnormal heart rate, so you want to be a little bit more leery.”