question for you experts...


been doing crunches, usually sets of 20 and anywhere from
5-9 sets total in a work out.
My lower back has sometimes felt very sore while doing the crunches...
I sit on a towel to keep my butt from getting sore on the tile, but
I'm wondering if I'm doing something wrong...it's not a good kinda hurt.
It gets so sore during the set that I cannot continue and get my abs
burning like I like to. Any ideas here?
What am I doing wrong?
thanks!

Yitz