Stand tall with feet about shoulder width apart.
Squat down, keeping your back neutral. Knees tracking in line with the toes, not collapsing inwards.
Drive your feet into the floor, exhaling as you jump upward explosively, fully extending your knees and hips.
Land softly on the ball of your feet, bending your knees to absorb the impact and repeat for repetitions.
Avoid collapsing your torso forwards, and don't let your back round as you descend. Pause in between repetitions if you cannot control the movement.