This is not a blog about hydration. Although I once went to war with a co-worker on the importance of hydration in life or death situations and I am blessed to understand that being dehydrated won't kill you, but it will likely reduce your performance.
Fluid by definition is the ability to move easily. The fluid we will discuss here relates to those poppy and cracky shoulders ya got there bub (Vermont voice).
It gets a little technical so feel free to skim and land on the last couple paragraphs.
This blog is going to detail the the necessary proximal positioning (ribcage position) for appropriate extremity use. Ok, set,
The Overhead Press. Glorified by Crossfit and butchered by high schoolers everywhere, is truthfully one of my favorite exercises. Not for any rehabilitation goal, or even for functional mimicry, it simply feels awesome to push-press enough weight to crush a small deer up over my head. Terrifying though is the thought that individuals walking into a gym with zippity oblique and serratus anterior strength often attempt this lift. Why does it matter? How do we get the necessary oblique and serraty-whatever strength to perform this lift appropriately? I'm so glad you asked...
The ribcage. Magnificent in its profound impact on our human system (although that could be said for any structure really). The ribcage does much more than house our heart and lungs. It also provides the basis of attachment for our shoulder blades. As our arms rise up over the level of our shoulder, the shoulder blade acts like a suction cup and approximates itself to the ribcage. This action creates "stability" in the joint. It is not by chance that this happens. The serratus anterior attaches along the inside of the shoulder blade (between the blade and the ribcage) and pulls from the shoulder blade to the rib cage during overhead motion.
This pull is key for producing force up overhead as well as when going into external rotation of the shoulder as occurs during cocking phase of a baseball pitch. Without appropriate approximation of the shoulder blade onto the ribcage the shoulder joint (the ball in shallow socket) will need to control substantial more force than when the scapula is approximated. So how do we approximate the scapula then? Do a ton of serratus work?
Yup! But that's not all!
Almost more importantly (if that were actually a thing) you need hold your ribcage in a position that provides the serratus an appropriate base to pull from (serratus pulls from the ribcage to the shoulder blade, effectively pulling the shoulder blade onto the ribcage). How do we get that?
You guessed it! ABS BABY!
More specifically the internal obliques. Sounds sexy, but its not. The internal obliques add very little superficial value to the glorified six pack (Rectus Abdominis), which means that sit-ups wont get you where you want to go. To some degree that is untrue, you will activate the IO's during sit ups, but you won't train the IO's to appropriate the position of the ribcage during overhead motion doing sit-ups. Instead, plank progressions and holding things that are manageable overhead will most effectively train this movement pattern.
As you can (kind of) see when the shoulder goes overhead the tendency to take the ribcage with it (picture on your right) is not ideal. This leads to anterior tilt (rounded shoulders) and leads to shoulder injury and reduced ability to control load overhead (performance).
What the model on the left depicts is appropriate IO activation holding the rib cage down, allowing the shoulder blade to approximate to the cage and remain somewhat vertical.
Did Abs and Serratus just become best friends? YUP!
Now try and squat, lol.
For appropriate overhead position, performance, and tolerance of load (not getting hurt) the ribcage must be held down by the internal obliques and the shoulder blade must be approximated to the ribcage by the serratus anterior. Period.
The way to train this motion is with plank progressions that cue scapular depression and protraction (push your ribs up into your shoulder blades). This is progressed by performing this exercise in progressively overhead positions without the sensation of jamming at the anterior superior shoulder (anterior tilt of the shoulder blade).
Do this, then crush workouts. And as always, if you are hurt, more than 3 weeks, find someone who knows what they are doing (typically is licensed) and has a business model where they can help you (typically can spend an hour with you per session).