3. Move your left foot back, keeping your leg straight, while pressing your heel toward the floor.
4. Move your hips forward until you feel tension in your left calf muscle.
5. Hold the stretch 10 to 15 seconds.
6. 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.