This is the first of a series on injuries in weightlifting and their prevention.
It is the nature of powerlifters, bodybuilders and weightlifters in general to push their physical limits. Progressive overload is a staple concept for building strength and mass. Like everything in this world, nothing worth achieving comes without some inherent risk. Maybe the appeal of these pursuits, to some degree, is the risk itself. Musculotendinous injury lies in wait for the unsuspecting lifter. Appreciation of the risks and proactive understanding of prevention will help keep those addicted to the sport of building muscle injury free. Two catastrophic injuries that plague the weightlifter, pectoralis rupture and biceps rupture, will be discussed with reference to mechanism and prevention.
Although the overall frequency of rupture of the pectoralis tendon is relatively uncommon, it is most frequently seen in association to bench press with heavy weight. 50-75% of reported ruptures are directly from bench press injuries. The pectoralis major tendon inserts on the proximal humerus and contraction leads to flexion, adduction and internal rotation of the humerus.
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An injury of the pectoralis most commonly occurs at the tendon insertion on the humerus. Only about 20% are at the musculotendinous junction. The transition from the eccentric phase of the bench press (lowering of the bar to the chest) to an explosive concentric contraction (pushing the bar away from the chest) is when the tendon is at greatest risk and most commonly when a rupture can occur. Anatomic studies confirm the mechanical forces on the tendon are greatest and disproportionate as the bar approaches the chest. This coupled with a rapid transition to concentric, explosive contraction of the pectoralis can lead to rupture. Not only is there a dramatic loss of strength (50% in some studies), but also a significant cosmetic deformity.
Using our knowledge of mechanism of injury and risk factors, a plan to minimize the risk of an injury of the pectoralis is feasible. Some of the recommendations should be self-evident to the experienced lifter.
Stretching prior to exercises are paramount to safety. Static and dynamic stretching with progressive warm-up sets should precede heavy bench press. This is especially true for those over 40.
Although there is little objective evidence of sentinel tendinitis, there is indirect evidence that some lifters at risk for rupture have a preceding inflammatory process of the pectoralis tendon at its attachment. An ultrasound study of contralateral pectoralis tendons in patients with a recent rupture showed significant abnormally inflamed tendons of the side that didn’t rupture when compared to comparable controls. This would suggest that symptomatic tendonitis could precede a rupture. Recognize tenderness at the attachment of the tendon on the humerus as a warning to be cautious with one rep maximum or personal best attempts until the symptoms resolve.
The risk of rupture occurs in the transition of the eccentric contraction (lowering the bar) into the concentric phase ( forcefully pushing the bar back up). The viscoelastic properties of the tendon are such that the rate at which the tendon lengthens affects the stiffness of the tendon. Stiffness is defined as resistance to change in length. The faster the bar is lowered to the chest, the stiffer the tendon becomes, increasing the risk of rupture. A descent of the bar under control will minimize the mechanical disadvantage of the inferior fibers that is associated with risk of rupture. Bouncing the bar off the chest will increase the risk of injury.
We know that the primary force associated with a pectoralis rupture is forced abduction from this study by Golshani. It is a well accepted point that, during the bench press, keeping the elbows flared (abducted) is problematic for the rotator cuff. It also is a position that increases the abduction force in the concentric phase of the lift causing an increased risk of pectoralis injury. By keeping the elbows tucked to around 45 degrees ( a position of relative shoulder adduction), the risk is minimized. By definition, a wider grip of the barbell tends to lead to the shoulder being in more abduction and therefore is undesirable. By the same token, a multigrip bar (Swiss Bar) or dumbbell bench press both allow a more neutral grip rather than the full pronation position of a barbell, which makes shoulder adduction more natural.
Although it is trite and repetitive, appropriate recovery is critical for prevention of injuries for the any level of weightlifting. Follow these suggestions for safe and rewarding strengthening.