Lie on your back and put a backpack (or some other thing that’s heavy) on your legs (This is the starting position).
2. Bend your knees, lift your pelvis and slowly extend your knees back to the starting position.
Lie on your back and put a backpack (or some other thing that’s heavy) on your legs (This is the starting position).
2. Bend your knees, lift your pelvis and slowly extend your knees back to the starting position.