HOW: Lay face down with a towel or strap around your ankle. Use the strap to pull your ankle towards your butt. Make sure to keep the pelvis tilted posterior (tucking your tailbone to keep a flat low back) while performing this stretch.
FEEL: You will feel the stretch on the front of your thigh.
COMPENSATION: Avoid arching your back as you perform this exercise. You can prevent this by tucking your tailbone underneath you prior to bending your knee.