Crescent Lunge strengthens your legs, including your hamstrings (back of thighs), quadriceps, (front of thighs), and calves.  It also strengthens your gluteus (buttocks), and core when done correctly. Crescent Lunge (or High Heel Lunge) is different from Warrior I. In Warrior I, your back leg is straight and your heel remains down. In Crescent Lunge, both knees are bent and the back heel is lifted.