Well, I either do the bike or, as a last resort, the treadmill for half an hour. Additionally, I work the upper body with weight machines. I do fly/delt, rowing, chest press, overhead press and a couple more. My goal is to tone and tighten as I lose. At my age, losing weight can leave you a bit "saggy", so I figure the cardio will work the legs, and the machines will do the other half!