1. Lie on your back with both legs straight. Pull one knee toward your chest, grasping behind the knee with both hands.
2. Straighten your lower leg as much as possible without letting your knee move away from your chest. Hold the stretch for 2 seconds.
3. Relax and return to the starting position.
4. Complete the set on one side before repeating with the opposite leg.
Be sure to: Keep your opposite leg on the ground by pushing your heel as far away as possible and contracting your glute.
You should feel it: Stretching the hamstrings of your bent leg and the front of the upper thigh on your straight leg.