Originally Posted by
Culican
I have had these exact same symptoms twice when losing too much weight. As soon as I gained a little weight (fat) back it went away. I first thought I had messed up something in my back. But after I had it happen twice and had it go away twice when I gained a little weight, I figured it must be from the pressure of my clothing (at the belt line) on a nerve which was left unprotected by the lack of fat.
At the time I did not use a belt for squats and deadlifts. Now weighing 189lb instead of 172lb (at 5'10") I do use a belt (coincidently an Inzer) and do not have the problem.