Jump squat in and out

Instructions

Stand up, feet together, back straight and head facing forward.
Lower your butt to your knees' level, keeping the weight on your heels, as if you are sitting on a chair.
Move back up explosively and jump.
Land by spreading your legs apart at shoulder-width and bending your knees.
Lower your butt like for the first squat.
Move back up explosively and jump.
Land with your feet together, bending your knees, and repeat.

Muscles