Burpee

1. Squat down with your feet straight forward, your heels on the ground and your knees tracking over your toes.
2. Jump back to a plank position, and land with your abs braced and without arching your back.
3. Drop into the pushup while keeping your tailbone tucked under and squeezing your shoulder blades together and down to your back pockets.
4. Finish the pushup and jump back to the squat position with your heels on the ground, knees straight forward and feet straight.
5. Jump upward and drop down to repeat.