ellejay. I'm only using 4lb weights (but will use heavier ones for chest fly from now on). I have knee issues at the best of times and was wondering if i could do this program. I've done the first 3 days fairly well. Just remember with your squats and lunges not to have your knee go over the level of your toes, and take it easy. I can't actually do all of the lunges with bicep curls myself. I don't want to overdo it because i know when my knee really plays up i can't do much exercise at all so best to be careful now. Did you have knee problems before? Hopefully the lighter weights will help!