If you want to grow you need to squat. 3 sets of ten reps done twice a week could pack and inch of muscle on your thighs and add 10 pounds of bodyweight. Try to keep you upper body erect with arched back and not leaning forward. Keep knees aligned with toes and lower yourself until thighs are a little lower than illustrated by the photo. Barbell squats add strength and development to thigh, butt, and lower back muscles. Thick spinal erectors come from heavy squatting and so does a big butt.
