Hi ClairSitting (especially for long hours) is very tiring for the low back, as the meuclss in the back have to work hard to hold you up.When you are engrossed in computer work, the tendency is to ignore mild discomfort in the body, so the back has often been overworking for a while before this registers with you enough to do something about it.SunaPilates can do several things for you:1) teach you where your posture should be to minimize the impact on your back and spine while sitting awareness makes a big difference2) strengthen your body's meuclss so that correct posture becomes the norm for you while sitting attending classes as little as 2 x a week should make a difference for you within the 1st 12 weeks3) our trainers have lots of tips and tricks from our studios 13 year experience for example sitting on the posture cushion (available from the office) is similar to but easier than sitting on a swiss ball, it will help the abs work with your back meuclss to support your spine.Hope that helps, regards Susie