The squat is a foundational human movement, important for strength training and everyday activities like sitting and standing. Although it appears simple, many people struggle to execute a full, comfortable squat. This difficulty is usually a combination of physical limitations, a lack of motor control, or improper movement habits. Understanding the specific root cause is the first step toward achieving a deeper, stronger movement pattern.
Mobility Restrictions That Limit Depth
A common reason for struggling with the squat is restricted passive range of motion at specific joints, which forces the body to compensate. Achieving a deep squat requires significant ankle flexibility, specifically ankle dorsiflexion. Limited dorsiflexion, the movement that allows the shin to move forward over the foot, prevents the knees from traveling forward enough to keep the torso upright.
When the ankles cannot flex sufficiently, the body shifts its center of mass to maintain balance, often causing the heels to lift. This limitation forces the torso to pitch excessively forward, transforming the squat into a hip-dominant movement with a rounded lower back. Tightness around the hips also restricts movement, particularly in the hip flexors and adductors, which must lengthen for deep flexion. If the hip joint lacks necessary flexion, the pelvis will tuck under to compensate, an error known as “butt wink.”
Stability and Strength Deficits
Even with sufficient joint mobility, the active ability to control the movement can be lacking, leading to stability and strength deficits. Core bracing involves creating 360-degree tension around the midsection, often achieved through a deep breath and tightening the abdominal wall. This action significantly increases intra-abdominal pressure, which stabilizes the spine.
A weak or poorly braced core cannot maintain a neutral spine, causing the torso to fold forward or the lower back to round under load. Gluteal muscles control the rotation of the femur and prevent the knees from caving inward, a fault known as valgus collapse. If these muscles are not adequately activated, the knees may collapse inward, placing undue stress on the knee joint. Upper back stability is also a factor, particularly in barbell squats, where the muscles of the thoracic spine must work to resist the weight trying to push the lifter forward.
Common Technique Errors
Beyond physical limitations, poor squatting can stem from simple, correctable errors in movement execution. One common technique error is initiating the squat by bending the knees first instead of simultaneously driving the hips backward and the knees forward. This knee-first approach causes the knees to travel excessively far forward over the toes, potentially leading to discomfort or an inefficient path. Instead, the movement should be initiated by “sitting back,” engaging the hips and allowing the knees to follow in line with the feet.
The “butt wink” is a frequent technical error where the pelvis posteriorly tilts and the lumbar spine rounds at the deepest point of the squat. While often a sign of exceeding mobility limits, it can also be a technique flaw resulting from poor motor control. This rounding places compressive forces on the lumbar discs, which is especially concerning when squatting with added weight. The choice of foot placement and stance width is another factor; an inappropriate stance for an individual’s hip anatomy can restrict depth and cause discomfort. Adjusting the toe-out angle or widening the stance can provide the necessary space for the hip to flex without mechanical interference.
When Pain Stops the Movement
The presence of sharp or persistent pain during the squat is a signal that should halt the movement immediately, as it indicates a potential tissue issue or structural problem. Sharp knee pain, particularly under the kneecap, may signal patellofemoral pain syndrome or patellar tendinitis, often exacerbated by poor tracking. Pain that feels like a catch, lock, or pop in the knee could suggest a meniscus tear, requiring a professional diagnosis.
Persistent low back pain, especially when accompanied by butt wink or lack of core stability, signals that the spine is not being held in a safe, neutral position. This may indicate a risk of disc or ligament irritation beyond simple muscle soreness. Any radiating pain, tingling, or numbness traveling down the leg should be taken seriously as a potential sign of nerve involvement. In these cases, the focus must shift from performance correction to safety, requiring consultation with a specialist for a proper assessment before resuming the exercise.