Today you may be sidetracked from going to the gym. Experts say you should exercise for at least 30 minutes a day for optimum health. Make time to get your heart rate up and burn some calories, while staying green at the same time. Find some stairs at work or home and climb up and down for 15 minutes straight. Cycling is an ideal aerobic activity. Go for a ride in the park. Or if it's too cold outside, challenge your friends to the ultimate snowball fight. That should get your blood pumping!