Starting Position: Stand in an athletic ready position with your feet hip-width apart, right leg forward, left leg back. Both arms are bent with the left arm in front of your body and the right arm behind your body. Prepare for the jump by leaning forward at the hips, keeping your weight back in your thighs, shoulder blades pulling down your back and abdominals engaged to brace your spine.
Jumping Movement: Quickly sink your weight back into your hips then explosively push both feet into the floor and drive your hips forward to launch your body into the air completely extending the ankles, knees and hips. As you jump into the air, keep your feet level with each other and parallel with the floor.
While you are in the air switch legs bringing your left leg forward and right leg back behind your body. Switch arms bringing your right arm forward and your left arm back.
Downward phase: As you land your left leg should be in front of your body and your right leg back behind your body. The most important components of the landing phase are correct foot position and avoiding excessive forward movement in your lower legs which places additional stress on your knees. Try to land softly and quietly on the mid-foot, quickly rolling toward the heels to in order to level the foot, making it parallel with the floor. Always push your hips backwards and drop your hips to absorb the jumping forces. Do not lock your knees on the landing in order to avoid potential knee injuries. Land with your trunk inclined slightly forward, head aligned with your spine and back rigid or flat. Keep your abdominal / core muscles engaged, bracing your torso to protect your spine.
Exercise Variation: Be sure to alternate the forward leg, when learning this exercise focus first on landing with control and resetting before another repetition, as you improve your strength and power progress to performing multiple jumps in a row.
It is suggested, you first learn how to squat and land before attempting to jump. Once you have mastered the hip-hinge mechanism, begin with small jumps, but emphasize your landing mechanics. Only progress to more explosive jumps once you have mastered your landing mechanics.