When Kent Benson, the former National Basketball Association player, came to the University of Indiana he could jump only 9 inches off the ground. That’s an embarrassing jump for a seven-foot All-American. One year later, he was able to jump three times that high because he had a good coach.
How high you can jump is determined by the force that you can exert when you contract your leg muscles against gravity. Strengthening your muscles in the same way that you use them in jumping will help you to jump higher. You strengthen muscles by exercising them against progressively greater resistance, such as lifting heavier weights. To be able to jump higher, you have to exercise your muscles against resistance in the same way that you use them when you jump. You can bend your knees and hips and straighten them by performing leg presses up while lying on your back, sideways while sitting in a chair, or down against the ground when you squat in the upright position.
Set up a schedule in which you lift moderate on Monday, easy on Wednesday and hard on Friday. Monday, after you finish basketball practice, do two sets of the heaviest weight that you can squat 15 times. On Wednesday, pick a lighter weight and squat three sets of ten. On Friday, use the heaviest weight that you can squat ten times, add weight and use the heaviest weight you can squat six times, and then add weight and squat the heaviest weight that you can squat three times. On days when your muscles feel sore or tight, skip your weightlifting workout.