I can nail any shot they throw at me, hauling the rig through a twelve-hour day without missing a frame. But my back screams by the wrap, my knees are shot, and I ice my shoulders every night. I'm at the top of my craft, and my body is quietly sending me the bill for every year of it.
More people experience this than they realize.
You're excellent at the physical work, and your body is paying the price.
If this sounds familiar, the Library can help you find the bigger picture.