If you train your quads using either holding a static position with your legs stretched out or doing full squat-like movements, both ways build your thigh muscles about the same amount — neither one is better than the other.

Doing static leg exercises with your thigh muscles fully stretched might grow the upper part of your thigh more than doing regular leg exercises that move through a full range, but both types of exercise end up making your whole quadriceps muscle about the same size.

If you're already someone who lifts weights, doing either static holds with your muscles stretched out or full-range weight exercises won't make the outer part of your thigh noticeably bigger in just six weeks.

If you lift weights the same amount and with the same effort, holding your muscles still (isometric) builds muscle just as well as moving them up and down (dynamic).

If you’re already experienced with weightlifting and train your legs twice a week for 8 weeks with hard sets, your muscles will grow whether you take short breaks between reps or not.

Muscles don’t grow evenly—when you train your thigh, the top and middle parts of the front muscle grow more than the bottom, and the side muscle grows the same everywhere.