Want to Lose Weight? Take A Hot Bath
It's hot. Working out? Even hotter. And yet, the best way to hack your next workout might start with a hot bath.
Yes, that sounds sweaty, exhausting, and unappealing, but research shows it produces better workout results in the sticky hot months than taking measures to cool yourself, like freezing workout clothes before wearing them or strapping on ice packs in preparation.
The science behind hot baths is simple: By dunking your body in really hot water, you acclimate to heat better, making your body sweat more to release internal heat. It also takes less time than slowly acclimating to hot weather by gradually extending the time spent exercising out of doors. One recent study found that runners who tried to acclimate to the heat—study participants prepped for a 5k in hot weather by pedaling exercise bikes at intense speeds in a 99-degree room for 90 minutes, five days in a row—improved their running times by 6.5 percent, according to The New York Times. (Their times were a tiny bit faster when they did heat acclimation and cooling methods, like ice packs and frozen clothes.)
Because forcing yourself to bike for 90 minutes each day in almost unbearable heat is not reasonable (and potentially dangerous, given the risk of heat stroke and nausea), the study author suggested to "lie in a hot bath, heated to at least 40 degrees Celsius"—104 degrees Fahrenheit—"for 30 minutes after a 30-minute run." Or, like the study participants, build up to the outdoor workout by doing heat acclimation in a hot bath in the days before.
In the long run, withstanding the heat is worth it: Heat training has been shown to improve cardiovascular health by expanding blood plasma volume, increase skeletal muscle force, and lower core temperature. It also makes training in cold weather easier, according to Outside. Something to keep in mind as you force your legs and lungs forward in the grueling summer humidity.
This story originally appeared on Esquire.
* Minor edits have been made by the Esquiremag.ph editors.