leanbody
man on a mission
yes use a belt and dont pull your stomach in but learn to push it out against the belt. This way you get support on the spine both sides. And see yourself having that much stronger posterior.
Great advice - and make sure it's really tight - like you can't slip your fingers in there between the belly/back & belt.
Milky (MOFO too) if your back still bothers you 3 weeks into the new routine, I'd recommend acupuncture. it's really great for back stuff - somehow it loosens up or relieves the muscle pressure and allows it to heal better. plus you may have your chee blocked...;-)