Integrate interval training into your workout. Interval training is a regimen that uses both low-intensity and high-intensity movements. The key is to vary intensity levels throughout the workout -- performing intense spurts mixed with periods of rest. Interval training improves cardiovascular health, boosts metabolism, increases stamina and more. It also helps you stick with your exercise program by alleviating boredom -- trudging along on the treadmill at the same pace can get pretty humdrum. High-intensity interval training, or HIIT, burns more calories and fat than just plodding along, which results in a faster metabolism. The only thing to watch out for when incorporating HIIT into your workout is overdoing it.