How to Avoid Weightlifting-Related Shoulder Injuries

Terms used in this article:

• Rotator cuff: Muscles (supraspinatus, infraspinatus, teres minor, subscapularis) that stabilize the shoulder joint and rotate the arm at the shoulder
• Internal shoulder rotation: Standing with your upper arm against your torso with your elbow at a right angle, rotate your upper arm inward until your hand touches your abdomen.
• External shoulder rotation: From the position you just attained by internally rotating your shoulder, rotate your upper arm outward so that your hand moves away from your abdomen, as you would when throwing a Frisbee.
• Trapezius muscle: Extends from the back of your head and neck down your central upper back and serves to raise the shoulders and draw them backwards.
• Range of motion: The number of degrees through which a joint can be rotated.

A recent article by Kolber et al. in the Journal of Strength and Conditioning Research (Vol 24, no 6, pp. 1696-1704, 2010) reviewed existing scientific research articles on shoulder injuries brought on by weightlifting. It noted that 25-35% of people who engage in resistance training sustain an injury severe enough to require medical attention and that 36% of such injuries are to the shoulder. The vulnerability of the shoulder is related to the high number of exercises that involve the shoulder, the great stresses the exercises place on the shoulder, and the unfavorable positions in which some exercises place the shoulder. In addition, many lifters do not warm up properly, select a balanced set of exercises, use proper lifting technique, or modify/eliminate exercises that cause pain. Major muscles are frequently worked to the exclusion of minor ones, leading to muscle imbalances. Shoulder muscles commonly injured include the pectoralis major, biceps, deltoid and rotator cuff group.

The Most Common Signs of Shoulder-Dysfunction Among Weightlifters:

• Reduced internal shoulder rotation range of motion
• Excessive external shoulder rotation range of motion
• Underdeveloped external rotation strength relative to internal rotation strength
• Underdeveloped external rotation strength relative to arm abduction (raising) strength
• Underdeveloped lower trapezius strength relative to upper trapezius strength
• Instability of the anterior (front) shoulder
• Tightness of the posterior (rear) shoulder

Common Pain-Producing Exercises
The following exercises in which the upper arm is raised to the side and parallel to the floor while the forearm is vertical put the shoulder in a fully externally rotated position and are considered hazardous:

• Behind the neck pull-down
• Behind the neck overhead press
• Overhead stack machine press in which the hands move rearward as the weight is lifted

Other exercises, although generally safe, also associated with shoulder pain:

• Bench press
• Incline chest fly
• Supine chest fly
• Dip
• Biceps curl

The following may help to prevent weightlifting-related shoulder injury:

• Discontinue any exercise that causes pain.
• If an exercise hurts, try variations that do not hurt (e.g. bench press with rolled up towel on chest to limit movement).
• Balance every push exercise with a pull exercise in the opposite direction.
• Balance exercises involving major body movements (e.g. bench press, pull-down) with those that stabilize and rotate the shoulder.
• Exercises that strengthen external shoulder rotation are particularly important (e.g. do the external rotation movement described above, resisted by weight stack cable or elastic band).
• Do strength exercises for the lower trapezius (e.g. rowing motions with elbows high and shoulders drawn fully back).
• Do flexibility exercises to increase internal shoulder rotation.
• Do flexibility exercises to stretch the rear shoulder (e.g. Stand with upper arm parallel to the ground. Grip elbow with other hand and pull arm horizontally across the chest).