You're going to perspire this summer. A lot. Sometimes just stepping out the front door in St. Louis is enough to cause your sweat glands to spew like Old Faithful. Sure, you could run back into the air conditioning. But to do so is to surrender. And we St. Louisans are a tougher lot than that. Besides, sweating is actually good for you: It removes toxins from the body (according to the 28 seconds of scientific research put into this article). So go ahead and break a sweat this summer with some of the following fun, outdoor activities.