Do you remember playing in the playground as a child? Can you remember some of the things you used to do? Some of the things that come to mind are swings, money bars, climbing and the flying fox. I remember on occasions at family gatherings we took turns while our uncle took us by the wrists and proceeded to spin around in circles like a helicopter while the mothers sit in the corner fretting that one of us would pop a shoulder out, but it never happened. In fact all these things, in reality was fundamentally contributing to strong, healthy shoulder joints.
In some way or another, all these things involve holding the arms overhead and having them distracted away from the torso. Developmentally, it was teaching and refining upward rotation of the scapula and reactive stabilisation of the glenohumoral joint and the scalula stabilisers.
If you are not currently doing hanging exercises in your training prorgam, the video below has some suggestions on how to start. I believe perfroming hanging drills as a warm up are effective at improving shoulder mobility and stability instantly as well as reducing the degeneration on the shoulder joint over the lifespan.
Have a look at the video below and play with these in your next gym session :)