1. Cross your right arm over your chest.
2. With your left hand, gently pull your right elbow toward your left shoulder. Keep your right arm straight.
3. Hold the stretch 10 to 15 seconds.
4. Repeat on the other side.
Stretching makes your muscles and joints flexible, preventing injuries, and stopping your muscles from cramping. Flexibility also allows you to move your muscles through their full range of motion. That helps you jump higher, reach further, and run faster.