Place your hands flat on the floor, shoulder width apart.
Extend your torso and legs fully behind you with only your toes and balls of your feet touching the floor.
Your body should be in a straight line, with your weight supported on your hands and toes only.
Starting with either leg, flex your knee and hip at the same time to bring your knee up and under your hip. Your other leg should remain fully extended. This is the start position.
Using an explosive movement, reverse the position of your legs, by extending the bent leg back and simultaneously flexing the straight leg until it is in the startposition.
Continue alternating in this manner for the desire amount of time.