It is nearly impossible to burn fat and build muscle in the same workout. The easiest way to gain muscle and lose the pounds is to start by adding on the muscle, start bench pressing, curling, etc. Do this for 2-3 weeks every other day so your muscles can repair themselves. I also recommend eating 4-5 meals a day and taking a Protein Supplement. Once you feel you are significantly stronger it is now time to tone your muscles and burn the fat. This means lift alot less weight more alot more repetions. Running and Swimming can quickly and effectively burn fat and tone your muscles.