How much protein do you need after a workout?
Any amount of protein is a good amount of protein. I would probably say anywhere from 10-30g. However, protein is not enough. With protein you need carbs, in order to transport the protein to all the muscles that need it. So, chocolate milk is a perfect after workout snack :) Perfect ratio of carbs and protein
Also, after about 40-50g of protein, the body is unable to metabolize more in one sitting, and you just pee it out. So if you're going to eat a chicken breast (25-35g of protein), you don't need a protein shake to up it to 50g of protein, because it's a waste of protein and it's rough on the kidneys.