Mountain Climbers 

1. Balance weight on palms and toes in a raised push-up position.
2. Kicking off with your left leg, keep your right leg planted as you curl your left knee in towards your chest, allowing your back to arch slightly. Keep your right leg straight.
3. As you uncurl your left leg and extend it out straight behind you as it was in the starting position, curl your right leg in towards your chest.
4. Continue this alternating cycle for one minute.