The bench press is a popular exercise for building upper body strength. However, this technically demanding movement places significant stress on the shoulder joint, which is the most mobile and least stable joint in the body. For many lifters, shoulder pain becomes a frustrating barrier to continued progress. Understanding the mechanical causes and underlying anatomical factors is the first step toward correcting the issue and returning to pain-free lifting.
Common Technique Errors
Shoulder pain often stems from errors in the lift’s execution. A common fault is allowing the elbows to flare out too wide, pushing the upper arm angle close to 90 degrees relative to the torso. This internally rotates the shoulder joint, compressing tendons and soft tissues, which leads to anterior shoulder pain. A safer position involves tucking the elbows so the upper arms form an angle closer to 45 to 75 degrees with the body, keeping the shoulder more stable.
The width of the grip also influences the strain placed on the shoulder. Gripping the bar too widely increases the distance the bar travels, placing greater stress on the joints and increasing injury risk. Research suggests that a grip width less than 1.5 times the bi-acromial width—the distance between the two shoulder tips—reduces compression forces. Conversely, a grip that is too narrow shifts the emphasis primarily to the triceps and can cause forearm misalignment, creating unnecessary torque on the elbow and shoulder.
Another frequent error involves a lack of scapular retraction and depression. Maintaining a tight, retracted scapula provides a stable, bony platform on the bench from which the arm can press. If the shoulder blades are allowed to protract, or round forward, the head of the humerus can drift forward, pushing into sensitive structures like the rotator cuff tendons. This stabilization also helps optimize the diagonal bar path, which should descend to the mid-to-low sternum and press back toward the starting point above the shoulders.
Underlying Shoulder Vulnerabilities
While poor technique acts as the trigger for pain, underlying structural or muscular vulnerabilities are often present. One common diagnosis is shoulder impingement syndrome, which occurs when the rotator cuff tendons become compressed during the lifting motion. This compression is often the result of poor mechanics, but it is exacerbated by weakness in the muscles that keep the humeral head centered in the shoulder socket.
Weakness in the external rotators of the rotator cuff is a significant factor because these muscles stabilize the joint against the forces of the bench press. When these stabilizers are inadequate, stronger, interior-focused muscles, like the pectorals and anterior deltoids, can dominate the movement. This imbalance creates a disproportionate pull on the shoulder joint, leading to a forward-rounded posture associated with functional impingement.
Limited mobility in the thoracic spine, or mid-back, can force the shoulder joint to compensate. An inability to achieve a slight upper back arch during the setup means the shoulder blades cannot properly retract and depress, robbing the shoulder of its stable base. This tightness can contribute to the “Upper Crossed Syndrome” pattern, characterized by tightness in the chest and upper traps, combined with weakness in the mid-back and lower shoulder stabilizers. Addressing this stiffness is a necessary precursor to achieving safe and effective bench press form.
Modifying Your Bench Press Routine
Implementing changes to your routine can alleviate pain and allow for continued training while addressing underlying issues. The first adjustment is a substantial reduction in the weight being lifted, often by 30 to 50 percent, to reduce overall joint stress. This temporary decrease in load allows sensitized tissues to calm down, enabling you to focus entirely on reinforcing pain-free technique.
Incorporating specific accessory exercises corrects muscle imbalances. Movements like face pulls, band pull-aparts, and external rotations directly target the often-neglected rear deltoids and rotator cuff muscles. These exercises should be performed with high repetitions and light resistance to build endurance and strength in the stabilizers, counteracting the dominant forces of the chest and front deltoids.
The warm-up protocol should transition to targeted joint preparation. Before benching, perform dynamic mobility drills that prioritize activation of the shoulder stabilizers, such as light dumbbell flyes or shoulder dislocations with a band or stick. This pre-lift activation ensures the rotator cuff is prepared to stabilize the humeral head under load, reducing the risk of strain during the working sets.
If the standard barbell bench press remains painful, temporarily substituting the exercise with variations can maintain strength. The dumbbell press allows the hands and shoulders to rotate freely, helping you find a less painful path. Alternatively, the floor press limits the range of motion by stopping the elbows when they hit the floor, eliminating the most vulnerable bottom portion of the lift. These alternatives allow the chest and triceps to be trained while giving irritated shoulder structures time to recover.
When to Seek Medical Guidance
While many instances of shoulder pain can be resolved through technique modification and focused accessory work, certain symptoms warrant professional medical evaluation. If you experience sharp, shooting, or radiating pain that travels down the arm, this may indicate nerve involvement or a significant structural issue. Pain that persists even when the arm is at rest or wakes you up at night is also an indicator that the inflammation or injury is beyond a simple muscular strain.
A sudden, acute event, such as feeling a distinct “pop” or tearing sensation followed by an immediate loss of strength or mobility, suggests a severe injury like a rotator cuff tear. If you are unable to lift your arm above shoulder height or if the pain has not improved after consistently implementing modifications for several months, consult a physiotherapist or orthopedic specialist. These medical professionals can accurately diagnose the root cause and prescribe a specific rehabilitation plan.