Why scapular protraction during some pressing exercises and not others?

June 18, 2016 11:12 AM

I know with an exercise like the bench press you should keep your shoulder blades retracted throughout. However, I've also read that with push ups some people recommend scapular protraction at the top. Testing it out, it does feel easier on the shoulders doing it that way. However, I'm having trouble understanding the mechanics of why that is the case. Where would, say, a standing cable press fall in this retraction vs protraction dichotomy?
posted by theshire to Health & Fitness (2 answers total)

First off, I am not a physical therapist, trainer, or otherwise credentialed; I am just a person who spends a fair amount of time reading about and practicing strength training.

My understanding is that the reason for scapular protraction at the top of a pushup is to extend the range of motion and to train the muscles which protract the scapulae. You'll miss out on some of the benefit if you don't protract, and you may set yourself up for an imbalance if you also train pulling motions such as inverted rows or pullups which feature scapular retraction.

There are two reasons I can think of to avoid scapular protraction in the bench press.

First: the bench press is an open-chain exercise, meaning your hand is not in a fixed position. This requires more stabilization than a closed-chain exercise like a push-up, where your hand is planted and cannot move. If you stick your arm out straight in front of you and compare protracted and retracted shoulder positions, you'll notice your extended arm moves around more freely when your shoulder is protracted. Keeping the shoulder retracted throughout the bench press helps you stabilize the load.

Second: your back is braced against the bench and should remain so throughout the motion. You need retracted shoulders to keep your elbows in position as you lower the bar (and, similarly, you will find your shoulders retracting somewhat as you lower yourself in a pushup unless you allow your elbows to flare way out). You can't protract your shoulders at the top of the lift without changing the point of contact between your back and the bench. Moreover, returning to the retracted position for the next rep while holding a heavy bar would be very difficult--you would probably have to rerack the weight in order to reset your shoulders.

A standing cable press is somewhere in between. You aren't bracing your back against anything, so in principle you can switch between protracted and retracted shoulders as you would in a pushup. But it is an open-chain movement, so stabilizing the protracted position will be difficult. I'd probably recommend against protraction for this reason, unless you're using light resistance for the specific purpose of training shoulder stability in this position. (For that matter, if you're already doing bench presses and pushups I'd recommend skipping the cable presses and finding another exercise to spend your time on.)
posted by egregious theorem at 2:41 PM on June 18, 2016 [1 favorite]

In addition to the two factors described by egregious theorem, I think a third is that retracted scapulas work better for pressing with an arched back. If you want to see the difference, try pressing a moderate weight in all four combinations of scapula retracted or not, back arched or not. To really eliminate the back arch, flex your knees up so your feet are on the bench by your butt.

People arch their backs for two reasons. From a biomechanical perspective, you've got more muscle in the lower pecs, and arching the back lets you use those more. Also, for competitive powerlifters, arching the back lets them touch the bar to their chest with less range of motion, which lets them record bigger lifts than they could if they had to bring the bar down another inch or two. And then everyone else does it because bench press technique is optimized for powerlifting because powerlifting is the only sport that directly incentivizes people to study bench press technique.
posted by d. z. wang at 6:56 AM on June 19, 2016