Originally Posted by
Carbonfiberboy
I was doing power work, sets of 12 with heavy weights, done very fast. I don't do any power work anymore. It seems to me that the very short period of high acceleration when one reverses direction could overstress connective tissue, and did once for me. Deadlifts from the floor or rack, or similar lifts, would be excepted.
My experience is that this is very safe for the lower body with suitable preparation, because that's what the lower body is designed to handle, but not such a good idea for the upper body. The moment of direction reversal happens to be the phase of movement that most stimulates gains in strength and power.