Select a box or step of a height appropriate to your abilities. Single-leg jumps will require lower boxes than double-legged versions, and caution should be used due to a higher risk associated with the exercise. To begin, stand 6-12 inches in front of the box. Your feet should be shoulder-width apart, your knees and hips slightly bent, with good posture throughout your spine. This will be your starting position.
To initiate the movement, lift one foot slightly off the floor to transfer the load to the working leg. Begin flexing the hips and knees into a quarter squat, generating an elastic force that will be used to power your jump. Swing your arms behind you in preparation for the movement.
Explode out of the hole, extending your hip, knee, and ankle of your working leg to propel you upward and slightly forward, striving for maximum height. Swing your arms forward as you jump for added momentum.
As you land on the platform, absorb the impact by allowing the hips and knees to flex into a partial squat. Use both legs to step down and return to the starting position. It is not advised to jump down from the box during this exercise.