Interval training involves alternating periods of moderately intense exercise that last one to three minutes with short, more intense exercise periods lasting from 30 seconds to a minute.

CNN: Is a shorter but harder workout better?

So by alternating doing a weight training workout one day in the gym, then going for a walk the next day, you can help speed up your recovery from your weight training workouts, reduce muscle soreness, and burn some bodyfat at the same time.

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