Just as your feet leave the ground, your calves power up to give you that last push into the air. This oft neglected muscle group is crucial for powering a big vertical leap. While your hamstrings and quads are the primary movers, even strong thighs can't make up for weak calves. As a smaller muscle group your calves are easy to train at home with a mix of strength and plyometric moves.
1. Calf Raises
This strength move is so simple to do and so effective. Your calves will be on fire, even if you just use your own bodyweight. Hold onto something for balance so you can focus on achieving full range-of-motion.
HOW TO DO IT: Stand on the edge of a step with your heels hanging off. Press up onto your toes as high as you can. Squeeze your calves at the top then lower down slowly, letting your heels come down as far as possible. Repeat for two to four sets of 15 reps
For increased difficulty, do one leg at a time.
Variations in your stance are beneficial because you don't always jump and land with your feet parallel. Include calf raises with your toes turned out or in for variety and dynamic strength.
2. Jump Rope
Jumping rope is basically like doing one small jump after another. Focus on using your calves for that last little lift off the ground to really activate them.
HOW TO DO IT: Hold one end of a jump rope in either hand. Step in front of the rope. Swing the rope forward over your head and hop over with both feet in sync it as it comes around.
Once you're proficient at jumping and pushing off your calves, do toe jumps keeping your knees almost straight and staying on the balls of your feet the whole time. Do five to 10 sets of 20 jumps each.
Increase the challenge by doing single-leg jumps.
3. Single-Leg Hops
This plyometric move strengthens the calves and the ankle extensors that absorb the force of your body landing on the ground.
HOW TO DO IT: Stand on one leg with the other leg bent and passive. Maintain a slight bend in the standing leg. Keep the hips, knee and ankle stable. Squat down slightly then rise up, hopping off the ground using the calf muscle of the standing leg for power. Land and go right into your next jump, then switch legs. Go for height with each jump. Do two to four sets of 15 reps.
Notice how a sprinter sets up at the start of a race. The last powerful push off the start comes from the calves. Although sprint training doesn't directly translate to vertical jumps, it trains the calves' ability to stretch and reflex repeatedly under intense load.
HOW TO DO IT: Plot a course in your backyard or front sidewalk that's 20 to 100 meters long. Get set and sprint as fast as you can to the end, focusing on pushing off your toes to really activate your calves. Take a brief rest in between, then repeat for a total of eight rounds.
If you have a hill outside your house, try hill sprints on your toes. You can also sprint up stairs on your toes.