Earn Weight-loss Extra Credit

Cardio is great weight-loss extra credit, and best of all, it can be done without fancy machines or equipment (beyond a good pair of shoes)! You can only train your muscles so many times in a week without overtraining them, which is counterproductive. Your muscles need adequate rest and recovery time for best results, but you can do as much cardio as you want to earn that extra credit. I mean, don't run a marathon every day, but you can jog, bike, use the elliptical machine, or swim pretty much as often as you want.