Not an expert, but a confusing aspect is open chain vs closed chain exercises.
Open chain exercises leave the foot or hand free to move (like swimming) and because of the lack of support they can actually exacerbate injuries. Instead of putting a joint under compression they put it under tensive strain.
Closed chain exercises are the opposite, the hand or foot is rooted in place (pushups, running, squats, etc) and because of this they add stability through the compression, BUT because of the compression they can also exacerbate injuries (especially because closed chain exercises are often weighted or involve repeated impact).
In the end, like most things, there is no one size fits all. In some situations closed chain is better, other open chain is better. For the average person it doesn't matter as much as most people think. If you're injured consult an expert for exercise to do, if you don't want to do that avoid exercises that cause joint pain.
Most of the studies are injury-specific and not in 100% agreement.