MUSCLES ENGAGED Obliques Many people put a lot of focus on working their abs but forget their surrounding neighbors; the oblique muscles. Obliques serve as stabilizers, and are used in almost every physical activity. Exercising your obliques should be a very important part of your workout program. Shoulders The shoulder is the most movable joint in the body. However, it is an unstable joint because of the range of motion allowed. This instability increases the likelihood of joint injury, often leading to a degenerative process in which tissues break down and no longer function well. Exercise Instructions Step 1 start in a standing position with your feet about shoulder width apart. Step 2 Bend forward at the hip and dynamically stretch your hamstrings as your touch the floor and walkout into a plank position. Step 3 Press your body back up and complete a plank-up on the side before walking back up to the starting position.