Q: I was reading your Shoulder Savers: Part I article and noticed your table on balance in training. My main question is concerned with overhead presses. These lifts are categorized as internal rotation of the humeral joint. When we do overhead pressing, the humerus is fixed in an externally rotated position, correct? Why then is this internal rotation?

A: Good question. It’s more out of necessity with the population in question than it is true functional anatomy.

You’re never really “fixed” in any sort of rotation; your humeral head is always going to be rotating in order to accommodate the degree of flexion/abduction. More external rotation = more subacromial space. This is also going to be affected by the position of the bar (front vs. back vs. dumbbells) and the chosen grip (neutral corresponds to more external rotation). But anyway…

Long story short, if you look at all the other exercises in the “right” categories, they’re the ones that – when used in excess – typically contribute to impingement. Overhead pressing is only going to make impingement worse, and a large percentage of the population really can’t do it safely. As such, it needed a place to go beyond just scapular elevation.

Additionally, while I can’t remember where I saw the data, there was a study that looked at relative EMG of the three heads of the deltoid and found that anterior deltoid (internal rotator) EMG activity was always higher than that of the posterior deltoid (external rotator). Consider that the posterior deltoid also leads to superior migration of the humeral head, and the external rotation contribution that you get with the movement is still going to have a sublte effect on increasing the risk of impingement.

All that said, debating the minutia isn’t what is important; what IS important is that lifters, trainers, and coaches start to appreciate who is and isn’t suited for overhead pressing. The more people I encounter, the more I realize that the “isn’t” crowd is a lot bigger than we previously thought.

Eric Cressey

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