Primary Muscle Group: Glutes

Muscle Groups Worked in This Exercise: Gluteus maximus, Biceps femoris, long head, Semitendinosus and Semimenbranosus

Preparation: Begin on your hands and knees. Place the band in the arch of one of your feet and take hold of both handles with a palms-in grip and with the band inside your arms. Raise the knee you are working towards your chest, assuring that your back is completely straight.

Breathing: Breathe in as you extend your leg backward and breathe out as you complete the extension and return to start position.

Execution: Slowly, extend your hip and leg and push your foot directly behind you. Stop when your foot forms a straight line with your body at hip-height. Pause, flex your hip and bend your knee, bringing in back toward your chest and start position. 

Comments: Don't forget to keep your abs tight throughout this range of motion. This will help to prevent your back from arching.