Sports Research Sweet Sweat Stick is activated by your elevated heart rate and may help the body sweat more during exercise. This topical gel works best during cardio, circuit, and high-intensity interval training. Can also be used while swimming, and in dry or infrared saunas. For optimal results, use with Sweet Sweat Neoprene Trimmers.Sweet Sweat is activated by your elevated heart rate improving activity + SWEAT to areas applied. Roll-on stick applicator makes it easy to spread on your skin & to get to those hard to reach areas.