Cause: Sweating helps the body stay cool, so it's normal for runners to sweat when they run. But hyperhidrosis, or profuse sweating, occurs when the body's normal cooling operations malfunction. Those with hyperhidrosis appear to have overactive sweat glands.
Prevention: Talk to your doctor about prescription-strength antiperspirants containing aluminum chloride. You may also want to use the antiperspirant on your feet, since heavy sweaters are prone to blistering. In extreme cases, medication or surgery may be necessary.
