I have tried deep squats, and I really like them. But I keep running into this problem in that I keep spraining muscles. Very specific muscles. The ones in the back that go over my right kidney. I have tried the squats on smith machines, hack machines, and even a piece of equipment in the gym that allows one to lay down prone and do you squats. It hits me with every variation. It is not a big sprain and usually goes away in about 3 or 4 days. My back is reasonably strong, so I don’t think it is a core muscle problem, but it is possible.
Any help would be appreciated