Why: By keeping your belly button drawn in and challenging your stability throughout your shoulders, core, and hips, you’re building strong abs.
How: Lie in a prone pushup position with forearms resting on the floor, elbows under shoulders and bent 90°. Push up off your elbows, tucking your chin so your head is in line with your body. Keep head inline with your spine, and belly button drawn in. Hold for one minute.
Prescription: 2 sets of 60 seconds with 60 seconds rest between sets.