If you are overweight but you have been working out should you still drink protein shakes or should you rely on your workout to make you gain muscle and lose weight?

Since muscle burns more calories than fat, you want to maximize the muscular growth stimulated by weight training. Since your muscles require protein to grow, it is important to get sufficient protein to get the maximum benefit from weight training.

In general, you should be ingesting sufficient protein every three or four waking hours (for a total of 5 or 6 small feedings daily). How much you ingest at each feeding depends upon your sex, your body size, and the quality of your training, but it will be (preferably from natural sources) at least 15 grams of high-quality proteins if you are female and 20 grams if you are male.