All put to the test at the same time, in a manner that I've done many times before, with weight added, but NOT while SUSPENDED. Definitely not while suspended with a 36 year old left shoulder that had (knowingly) been weakened (structural integrity, not soft tissue) by 315-365 pound chest presses (heavy for me) from all sorts of angles, AND...instability of the LONG HEAD of my left bicep as it attaches within the shoulder.
LISTEN UP ALL YOU SUPER "PRESS-STRONG-PRESS-HEAVY BEASTS!": This is what kills many - MANY Shoulder Joints That Never ARE THE SAME AGAIN in aging
lifters/bodybuilders! This is common - and occurs little by little with wear and tear that is often silently inflammatory (no pain felt whatsoever, just...um...noises that weren't ever there before; clicks, pops, low level rubbing or grating /rubbing/catching sensations and sounds...IT IS INEVITABLE with what we do. What is happening EXACTLY, and WHAT CAN WE DO?
As early as the 3rd decade of life (2nd decade of lifting-LIFE...haha-love it - like that?!) a unique and sneaky structure called the TRANSVERSE HUMORAL LIGAMENT (of the Biceps Brachii) that literally holds your GH joint together (the "head" of your arm bone or humerus) from tearing off your torso...EVERY SINGLE REP of EVERY SINGLE REP you do and have ever done on the bench...from any angle. If its a chest press and pecs are activated, the THL is deep within that monstrous mound of a shoulder...flipping you off the whole time and laughing.
It has to do with axial compression combined with unwanted rotation and poorly designed (sorry God) joint levers which allow shear or even the prevention of shear to promote STRUCTURAL COMPROMISE and progressive weakening of the key structures.
Actually nothing in the body ever really works alone, but in this case, the THL is pretty much getting jumped in the parking lot and all your juiced up buddies, from semi-pro explosive strength and power athletes to trained combat sportsman skilled to handle this very thing - all types of competitive amateur and pro-level MMA hybrids: are standing around watching, waiting, and ignoring their THL buddy get wrecked. Why?
In the case of the shoulder - specifically the STRUCTURAL INTEGRITY of the shoulder, all the mass, strength, power, and hypertrophy that you've built AROUND the joint, can do nothing to prevent the eventual wear and tear of the THL. No matter how big and strong (and even balanced) these surrounding torso muscles get, they just CAN'T GET-BETWEEN YOU, and the POINT OF DAMAGE.
THE CONTACT AREA where trauma happens from the OVERLOAD and the STRAIN occurs, happens time and time again; perfectly and repetitively. Unfortunately, if you are one of the few who built real chest size (44+ inches) from REAL progressive effort, you've routinely OVERCOME significant OVERLOAD. This is, the only genuine way to GROW mass throughout a completely developed CHEST.
Heavy, repetitive chest pressing or "horizontal A-Bduction in the transverse plane"; is a mechanically ideal human motion we are all capable of doing. As we become capable of 300lbs+ in this unique motion, the magnitude of forces generated through the THL literally pulls the shoulder off the body - little by little.
The MECHANISM (how this occurs): The transverse humeral ligament - since it is literally what holds the long head of the biceps brachii tightly secure within the GH joint, is essential to the shoulder's structural integrity (=what you can't consciously or 'actively' control in order to promote joint stability). As the THL becomes compromised over time, it begins to pull at the labrum - the inner casing of the shoulder joint that gives it congruency (think of it as a delicate washer for a nut or screw that prevents stripping when you tighten it all the way). What happens when that washer is stripped? Exactly, loosey-goosey and no 'bite' between the bolt/screw and the surface. In the human shoulder, this is like making the 'socket' of the 'ball and socket" joint, much, much bigger.
The result? A very poor fit of the shoulder 'ball' in the shoulder 'socket'. NOT good.