This article is going to show how u can do weight watchers for free, but first off, lets see why weight watchers is so successful. The 4 pillars of success; Food, exercise, behavior & support.
1 Hip muscles. Lunges work all of the gluteal muscles in the hips, primarily the gluteus maximus that is used to extend your hips. Taking large steps during a lunge can further engage this muscle. The gluteus minimus and gluteus medius are also used to stabilize your body throughout the lunge.  Thigh muscles.
For these reasons the Side Lunge is an excellent lower body exercise to compliment the lower body mass building exercises like the squat and the leg press. Main Target Muscle(s) Worked: Gluteus Maximus (glutes), Gluteus Medius/Minimus (Abductors), Quadriceps (quads), Adductors.