Jennifer was the only one in the gym who considered her workout to be an exercise in futility, since the men all appreciated that her boobs were still bouncing long after she got off the treadmill.
The condition that people with fibromyalgia claim they have that prevents them from engaging in physical activities that have been shown to significantly help their "disease."
Joyce: Because of exercise intolerance, I cannot workout for more than 10 minutes.
Billy: Hmmmmm, are you sure? Or is it because you weigh 300 pounds? You know Joyce, I know of a really good water aerobics class.
The stupidness that occurs during and after intense physical activity, where the body's limited bloodflow is directed towards the muscles instead of the brain.