A side squat, often called a lateral squat, is a compound lower-body exercise that involves moving the body side-to-side (frontal plane), unlike the forward-backward motion of a traditional squat. This variation shifts muscular demand to target different muscle groups for movement and stability. The side squat requires a stepping motion and a unilateral descent, making it a powerful tool for building strength and challenging balance.
Primary Muscle Activation
The side squat places distinct emphasis on the gluteal complex and the quadriceps of the working leg to drive the movement. The gluteus medius and gluteus minimus are heavily recruited to stabilize the hip and prevent the knee from collapsing inward during the descent. These smaller gluteal muscles are responsible for hip abduction and are significantly challenged by the lateral shifting of the body’s weight.
The quadriceps, particularly the vastus lateralis, are the primary knee extensors. They work hard to control the lowering phase and powerfully extend the knee to return to the starting position. The quadriceps control the flexion of the knee joint, and this unilateral loading pattern allows for specific strength development in the frontal plane.
The gluteus maximus on the working leg acts as a powerful hip extensor, especially when pushing out of the bottom position. The lateral motion requires the hip to hinge and extend while simultaneously managing side-to-side force. This combination of hip extension and abduction makes the side squat effective for developing posterior chain strength.
Key Stabilizers and Auxiliary Muscles
While the glutes and quads are the main drivers, auxiliary muscles are activated to maintain alignment and control the range of motion. The adductor magnus, a large muscle of the inner thigh, is heavily involved in the side squat. It works to stabilize the pelvis and eccentrically controls the straight, non-working leg as it stretches to the side.
On the working leg, the adductor magnus assists the gluteus maximus in hip extension during the ascent, particularly when pushing off the ground to return to the center. The hamstrings are also engaged, contributing to hip extension and providing knee joint stability. They work in concert with the glutes to control the deceleration phase of the squat.
Deep core muscles, including the transverse abdominis and the obliques, maintain a stable torso and prevent spinal rotation. Because the weight shifts significantly to one side, the core must brace powerfully to keep the hips square and the spine neutral. This stabilization role is crucial for safely transmitting force through the lower body.
Technique and Common Form Errors
To perform a side squat effectively, begin standing with feet hip-width apart, then take a wide step to the side, shifting weight onto that foot. The toes of both feet should remain pointed forward throughout the movement to ensure proper knee tracking and hip engagement. As you descend, push your hips back and bend the knee of the working leg, keeping the trail leg straight.
A common technique error is allowing the knee of the working leg to collapse inward, known as knee valgus, which places stress on the knee joint. To correct this, focus on driving the knee outward, aligning it directly over the ankle and middle toes. Another mistake is an excessive forward lean of the torso or rounding of the lower back, often called a “butt-wink.”
To avoid rounding, actively brace the core and maintain an upright chest, squatting down as if sitting into a chair behind you. Lifting the foot of the straight leg or allowing it to rotate can diminish the stretch on the adductors. The depth of the squat should be controlled by your hip mobility, aiming for a point where the thigh is parallel to the floor without compromising form.