Strengthens: quads, butt, hamstrings, lower back
1: Stand with your feet shoulder-width apart and toes pointed slightly outward.
2: Lower down into the squat position. (Remember to never let your knees go beyond your toes)
3: Engage your core and jump up explosively.
4: As you land, lower your body back into the squat position to complete one rep. Land as quietly as possible, which requires control.
Image from womenshealthmag.com
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