I'm doing FB Strong at the moment and I've started to worry whether I'm doing lower body exercises correctly. I feel pretty much every exercise (squats, side squats, lunges etc.) in my glutes and sometimes in the back of my thighs, but almost never in the quadriceps. Jump squats and pistol squats are the only ones that really make my thighs burn. I also never get sore in my thighs, just the glutes. Is this normal or am I doing something wrong?