Circuit 2, Exercise 2: Squat With Hamstring Curl Start in a standing position, with your feet slightly wider than shoulders-distance apart. Squat down until your hamstrings are parallel with the ground, keeping your legs in line with your knees and chest lifted. Return to standing and flex one knee, bringing your heel up toward your butt. Squat again and repeat, lifting the opposite heel to your butt. This counts as one rep. Repeat for 30 seconds. Image Source: Gold's Gym