before you heat up in exercise, is the advice du jour, according to Reuter’s.

Researchers found that when they outfitted male cyclists with special “precooling” garments before a workout in the heat and humidity, the athletes showed cooler body temperatures, lower heart rates and less sweating.

The cool down came courtesy of shirts and pants with tubing that allowed cold water to run through the clothes. Other studies have shown that a pre-workout dip in a cold bath or exposure to cold air can help exercisers lower their odds of heat strain in hot, humid weather.

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Physical activity causes the body’s core temperature to rise, with hot, humid weather spurring a particularly rapid ascent; at a certain point, an exerciser must slow down or risk heat-related illness. The idea of precooling is to increase the body’s heat tolerance by starting exercise with as cool a body temperature as possible.