This exercise is designed to stretch the hip flexors, calves, and groin muscles. As with all stretching you should only do them after an adequate warm-up to avoid injury.
Instructions
Start this stretch in a lunge position. The front leg should be bent, the other stretched out behind your body. Both arms should be bent and touching the ground beside your front leg.
To start this stretch, lean your weight forward into the front half of your body, and your bent leg. This should stretch out the upper part of the back leg. You will also feel a pull in your calf muscle. Hold for 3-5 seconds and switch legs.
Do 2-3 reps per leg.