Every so often, about midway through the month, it happens. The sun goes down, the full moon glows a bright bluish white in a dark, endless sky, and millions of Americans plant their butts by the TV. Not me. I'm thinking about getting my heart rate up, maybe somewhere outdoors, and believe it or not, I'm not alone. Outdoor activities and fitness of all kinds take place every month under a full moon, suiting unrepentant night owls like me just fine.