I too am limited on exercising . I will tell you some tricks that I have learned in order to tone up some. First of all ( and yes I know this sounds odd but believe me it works ! And you can start doing this while sitting ! ) take a deep breath now slowly let it out all the while holding your abs as tight as you can and count as high as you can before having to take another breath . Do this all through out the day and you will be supprised at how you will really feel those abs ! When I do this ( and yes I still do ! ) I try to do this at least 5 times in a row , and then slowly build up until you can do this about 10 times and also keep trying to increase the exhale number going up higher as your abs are tighting . Now this is really a great workout , once you can work you way from sitting to standing up , bend over slightly with your hands on or even just near your knees you will feel this inhale & exhale exercise in your abs , back , and thighs ! If you want some more ideas just let me know ! I truely hope this will help you and at the same time giving your back a light workout ! Please let me know if it helps you too ! Good luck ! Cheryl