The adductor muscle group, situated along the inner thigh, is often overlooked but plays a significant role in the squat. This group consists of five muscles—the adductor magnus, longus, brevis, gracilis, and pectineus—whose primary function is to bring the legs toward the midline of the body (adduction). Whether a standard squat effectively trains these inner thigh muscles depends on their specific function during the lift and the technique employed.
How Adductor Muscles Stabilize the Squat
The adductors are actively involved in the squat, primarily acting as synergists and stabilizers rather than being the main driving force. Their involvement ensures proper alignment of the femur relative to the pelvis and the knee joint. They work in tandem with the glutes to control the movement, particularly when descending and ascending with heavy loads. The largest of the group, the adductor magnus, acts as a powerful hip extensor, especially during the deepest portion of the squat.
When the hip is deeply flexed, the fibers of the adductor magnus are optimally positioned to assist the gluteal muscles in driving the hips upward. Research suggests that this muscle can contribute over 50% of the net hip extension moment when lifting out of a deep squat position.
Beyond generating force, the adductors provide necessary stability and help regulate knee tracking. They work to resist the inward collapse of the knees, a movement known as knee valgus, which can occur during heavy or poorly controlled squats. The adductor longus and brevis also contribute to this stabilizing function throughout the entire range of motion.
Squat Variations That Increase Adductor Focus
While a conventional squat engages the adductors, certain variations can intentionally shift more of the workload to the inner thigh muscles. The most effective way to increase adductor recruitment is by modifying the stance and foot positioning. These changes alter the biomechanical leverage and the length-tension relationship of the adductor muscles. The Sumo Squat is the most well-known variation for targeting the adductors, requiring a significantly wider stance than shoulder-width with the toes turned outward.
This position places the adductor longus under a greater stretch, especially in the bottom of the movement. During the concentric (lifting) phase of the Sumo Squat, electromyography (EMG) studies show greater activation of the adductor longus compared to narrow-stance back squat variations. To maximize this effect, lifters should focus on maintaining an upright torso and pushing the knees out actively to track over the feet. Deeper squatting also naturally increases adductor involvement because the hip is placed into a more flexed position, stressing the adductor magnus as a hip extensor when initiating the ascent.
Comparing Squats to Dedicated Adductor Training
The squat is highly effective for training the adductors in a functional, compound manner, but it may not be the optimal tool for maximizing strength or hypertrophy in this group alone. Squats train the adductors in coordination with the quads and glutes, which is excellent for overall athletic performance and stability. However, they rely on the adductors primarily in their role as synergists or hip extensors, rather than solely as adductors (bringing the legs together). Isolation exercises, such as the adductor machine or cable adduction, allow for a more targeted application of load and volume directly onto the inner thigh muscles. These movements permit training the adductors through their primary function of hip adduction, which is not the main action in a squat.
For individuals with specific goals, such as maximizing inner thigh muscle mass or recovering from a groin injury, dedicated isolation work is often recommended. Squats are an excellent way to build functional strength and stability in the adductor group as part of a whole-body movement. For specialized strength development, injury prevention, or targeted muscle gain, supplementing squats with specific, isolated adductor exercises provides the most comprehensive approach.