One arm static push up

Place one fist on the ground and keep your body straight in the up position of the push up. Keep breathing and count your heartbeats until you feel tension starting to build. Move the free shoulder to free the tension from setting in and repeat for the other side.
It is a simple drill which will allow you to build a healthy relaxed body in movement and also allow for recognition of areas where you do not pay attention. Keep your body straight and your breathing constant.