Q: In addition to my weekly strength-training workouts, how much cardio should I do during the week? I'm a 32-year-old who hasn't done very much exercise since high school gym class. - N.H., Detroit, MI

A: Cardio, which is short for cardiovascular, is any kind of exercise that strengthens your heart and lungs. Walking, running, swimming, bicycling, and skipping rope count as cardio workouts. Exercise research suggests that you can lower your risks for heart disease with three 20-minute cardio workouts during the week. However, if your goals are loftier and you want to lose weight, which means burning more calories, you'll need to walk, run, bike, or swim for at least 45 minutes five or six times a week.

Source: fitlinxx.com