★★★★★
I do 200 - 400 sit ups every day and this has kept my back pain away for 22 years. I actually have a waist .. Do not look for sudden Abs and say this does not work .. what you are after is the "Strong Core " start slow do one and work up to 2 then 3 then 10 each and then another 10 then another. Doing these exercises is better than any back pain ... I know.