Legs, Glutes, Hips
1. Stand with feet hip-width apart and arms at the side of your body.
1. Bring the heel to your buttocks by contracting the hamstring muscle.
2. Return your foot back on the ground, and bring the other heel up to your buttocks.
3. Repeat with alternating heels and gradually building up speed.
1. Engage (tighten) your core.
2. Make sure your spine is neutral and open your chest.
3. Land on the balls of your feet, not on your heels.