MUSCLES ENGAGED Glutes Gluteal Muscles (Glutes) are one of the strongest muscles in the body and are the connecting point between your legs and back muscles. Glutes are used in a variety of actions from moving the leg to extending and rotating the hip, as well as extending and rotating the trunk of the body. Back (upper) You can’t see your back without a lot of effort, but this doesn't mean you shouldn’t train it. Back exercises consisting of both back stretching and back strengthening is very important to your health and overcoming back pain. Equipment Used Bosu The BOSU balance trainer stands for "Both Sides Utilized" and is most often used for balance training, various athletic drills and aerobic activities. Exercise Instructions Step 1 Start on all fours on top of the Bosu with both feet off of the floor. Step 2 Lift one leg off of the Bosu and softly extend your knee. Make sure to keep your knee and foot in line with your hip. Step 3 Return your knee back down to the starting position and repeat.