Begin in plank position with the arms and body straight and shoulders over the wrists. Keep the 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.
Straighten the arms, coming back to plank position.
This counts as one rep. If this is too hard, rest one or both knees on the floor.