Im not sure I have the same exact issue, infact I doubt it, but years ago my right shoulder gave out while doing a set of dumbell presses and has bothered me ever since. Recently my left shoulder has been a problem as well. I don't even lift heavy anymore, as Ive transitioned to more of a runners physique, but even pushups aggravate it. Im not sure what the issue is as it doesnt cause me enough discomfort to get it looked at. But yeah, as you get a few years older you start noticing little things that start to become issues.
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