Standing with a much narrower stance while you squat targets the inner thigh, inner quad, and inner hamstring. There is no reason not to multitask on this move — so work your arms too. Here's how:
Begin standing with your legs together, arms raised to shoulder height with elbows bent, holding weights by your ears.
Squat toward the floor by bending your knees and reaching your bum backward, as if you were sitting in a chair. Keep your legs squeezing together. Focus your weight into your heels. While squatting, raise your arms overhead into a parallel position.
Return to starting position by pressing through your heels while bending your elbows to lower the weights back to shoulder level.