With your palms flat, raise onto your toes in a high plank position. Keep your hands directly below your shoulders, feet at hips-distance apart, and core engaged.
Bend the elbows behind you and lower your chest to the floor. Keep your upper arms tight to your body so your elbows are against your ribs on both sides. Engage your core and keep your back flat throughout the movement.
Straighten the arms, coming back to plank position.
This counts as one rep. Complete 10 reps.
You can modify this move by dropping down to your knees, as Graham shows.