Minute One: Mountain climbers
Start your 20-minute blast by getting your heart pumping. Mountain climbers are similar to running in place. Begin in a sort of a sprinter’s starting position, hands resting on the ground about shoulder-length apart, with one leg straight out behind you and the other bent so that your knee is near your chest. Jump the back leg to the front position and the front to the back simultaneously, then repeat for a minute. Make sure to keep your back straight.
