How do I go about training with weights when I am about 50-70lbs over weight. I do cordio 3-4 times a week 30-50 mins of it. Alternate my days with weight training. I do 3 times a week of weight training. Right now I am working the whole body. I do 3 sets of 12 uppper and 3 sets of 15 lower with moderate weight, that when I finish the last set I can barely lift the last rep. I am some what sore the next day and feel what body part I worked the day before and feels really really good. I was just wondering that since I am over weight how many set and how heavy should I lift. I do not want to bulk up or anything because I am trying to loose all these weight 80lbs. I know that muscle burns fat but how do I do it. I need some info...