Muscles Used In A Side Lunge

Performing the side lunge involves standing with your feet about shoulder-width apart, stepping sideways with your left foot, allowing your hip to rotate outward about 45 degrees, squatting on your left leg until your thigh is parallel to the floor, reversing to the starting position, and repeating the same movement with your right leg. You can perform the side lunge with a barbell, dumbbells or without any external resistance. The exercise targets a variety of muscles within your thighs.

Gluteal Muscles

The gluteal muscles, or buttocks, include the gluteus maximus, which extends your hip, and the gluteus medius and gluteus minimus, which abduct your hip, separating one leg from the other. The side lunge emphasizes the gluteus maximus, especially if you take a long step, according to ExRx.net. The gluteus maximus contracts powerfully to control the speed of movement during the downward-movement phase of the side lunge and to extend your hip during the upward-movement phase. The other two gluteal muscles contract to move your foot through the air and to stabilize your hip joint when your foot is planted.

Hamstrings

The biceps femoris, semimembranosus and semitendinosus muscles make up the hamstrings muscle group, which span the back of your thighs, crossing both the hip and knee joints. The hamstrings assist the gluteus maximus with hip extension and serve as the primary knee flexors. They only serve the former purpose, however, when you perform side lunges, because the force due to gravity facilitates the knee flexion range of motion during the downward-movement phase of the exercise.

Hip Adductors

The hip adductors include the adductor brevis, adductor longus, adductor magnus and gracilis muscles, which lie within the inside of your thighs. These muscles cooperate to pull your upper leg toward the center of your body. The hip adductors on your extended leg---the leg that you don't step with---contract during the upward-movement phase of the side lunge, helping you to stand up and return to the starting position.

Quadriceps

The quadriceps muscle group, or quads, consists of the rectus femoris, vastus intermedius, vastus lateralis and vastus medialis muscles, which run vertically within the front of your thighs. They are the primary knee extensors, and the rectus femoris also helps flex your hip. The side lunge emphasizes the quads, more than the hip extensors, if you take a short step, according to ExRx.net. They contract eccentrically---while the muscle fibers lengthen---to help control the speed of movement during the downward-movement phase of the side lunge, and concentrically---while the fibers shorten---to extend the knee during the upward-movement phase.