Q: Is there any harm to performing behind-the-neck lat pulldowns? A trainer in my gym told me they can be dangerous.
The trainer was correct. As a general rule, you should avoid any exercise that requires pulling or pushing a weight behind the neck. The problem with these moves is that they place the shoulder joint in a biomechanically disadvantageous position. Because the shoulder joint is so mobile – with freedom in all planes of movement – it is also highly unstable (increased joint flexibility necessarily results in decreased stability).
In the finish position of the behind-the-neck lat pulldown, the humerus (upper arm bone) is forced back in a manner that simultaneously causes extreme abduction and external rotation of the shoulder joint. This places a great deal of stress on the shoulder capsule, which can cause damage to soft tissue structures, especially the small rotator cuff muscles. Worse, repeated use of the exercise can cause stretching of the shoulder joint ligaments, increasing the chance of permanent deformation. Over time, the ligaments can become so loose that surgery is required to reinstate stability, setting back your training efforts for months.
There’s also a tendency to pull the neck forward and downward during performance, increasing the prospect of injury to the cervical spine and corresponding muscles and ligaments. There is even the danger of vertebral trauma if the bar is pulled down too hard on the spinous process. Given the fact that studies have shown the behind-the-neck version is less effective than other variations of lat pulldowns, there is no reason to include it as part of your training arsenal.