Looking to rev up your metabolism? You may want to do two short, high intensity workouts instead of just one. According to Dixie Stanforth, metabolism expert from the University of Texas at Austin, two smaller workouts can be just as effective as one. Why? Well apparently our metabolism stays revved up for at least an hour after a high intensity workout. So you do the math. Two high intensity workouts means that you're able to boost your metabolism for more than two hours. Pretty good for someone who doesn't have a full hour to work out, but can fit in short workouts in the morning and at night.