If your joints don't move and your muscle doesn't appear to lengthen during the exercise, you've done an isometric exercise. Adding these to your sprinting warmup helps maintain muscle strength and can help you with your speed. Always check with your physician first, especially if you're unconditioned or have a chronic health condition. Due to muscle tension, isometric exercises can increase your blood pressure.
According to exercise scientist Tom Seabourne and wellness expert Scott Cole, a strong core is important for sprinters. The authors, in their book "Athletic abs: Maximum Core Fitness Training," equate a strong core with powerful sprinting ability. Front planks tone the erector spinae -- the long muscles flanking your spine -- and your stomach muscles (specifically your rectus abdominus and transverse abs). Lie down face first with your elbows bent and toes tucked under. Tuck your elbows next to your body and tighten your abs and thighs. Slowly come up on to your elbows. Push up, moving your upper body and pelvis from the floor. Keep your body flat as you breathe. Keep your shoulders over your elbows and stabilize your hips to keep them from drooping. Hold the plank until you can't tolerate the tightening in your abs and thighs.
Straight Leg Raises
Straight leg raises are ideal for toning a sprinter’s quads. The quads are responsible for bringing the leg forward as your walk or run. Working this muscle helps you gain sprinting speed, notes the author of "The Art of Sprinting" Warren Doscher. To do a straight leg raise, lie down and bend both legs. Extend the left leg to a 45-degree angle, holding it in this position until your feel tightness in your quads. Lower the leg and repeat until fatigued, then switch legs.
Standing Leg Extension
You'll need a cable or resistance band to do standing leg extensions, but the payoff is worth it. The exercise will put speed in your sprint as it tightens your quads, which according to Doscher, helps with speed. Tie the band to a stable structure, then stand next it. Attach the other end to the ankle furthest away from structure your tied the band, and place your feet hip-width apart. Tighten your abs, straighten your back, and pull your shoulders back. Move the anchored foot slight forward, then lift it, moving the leg out to the side one to two inches. Inhale as you move your leg in and down. Continue until you feel tightness and burning in the quads, then switch legs.
Walls sits develop your quads with no equipment needed, which further enhances your ability to sprint down the lane. Stand against a sturdy wall or flat surface. Slide down, squatting as you go until your knees are bent. If your knees go into a full 90-degree lunge, you've gone too far. Hold the slight bent position for 30 seconds, or until you feel a burning tightness build in your quads. Stand and repeat the exercise three times, resting for 30 seconds in between repetitions.
- American Council on Exercise: Front Plank
- National Basketball Association: Building Strong Knees
- American Council on Exercise: Standing Leg Extension
- The Art of Sprinting: Techniques for Speed and Performance; Warren Doscher
- Athletic Abs: Maximum Core Fitness Training; Scott Cole, Tom Seabourne
- The MayoClinic.com: Are Isometric Exercises a Good Way to Build Strength?
- Jupiterimages/Pixland/Getty Images