Different leg exercises make different parts of your thigh muscles grow bigger—leg extensions grow all parts of one muscle, while squats mainly grow the middle part of another.

Leg extensions make the whole front of your thigh muscle grow evenly, while squats mainly make the middle part of a different thigh muscle grow.

Different leg exercises make different parts of your thigh muscles bigger — leg extensions grow the front part, squats grow the lower outer part.

Doing leg extensions makes the front thigh muscle grow more evenly along its length than doing squats, which don’t stimulate that muscle as much.

Which leg exercise you choose matters: leg extensions grow the front thigh muscle more, squats grow the lower outer thigh more and make you stronger at squats—but both help you get stronger at leg extensions.

Doing leg extensions for 8 weeks makes the front thigh muscle bigger along its whole length more than doing squats, especially near the knee.