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. Back (middle) Middle back muscles are very important as they help to support and strengthen the core muscles at the front of your body. Exercise Instructions Step 1 Start by laying on your side with your feet one on top of the other and your arm placed squarely underneath you. Step 2 Lift your body up maintaining a solid bridge while supporting your body weight on your one foot and forearm. Step 3 Hold this position for desired length of time or until your hips begin to sag and you can no longer maintain a solid bridge.