In the fitness world it is pretty much considered dogma that you should drink a protein shake immediately after training. Some people seem to think that if their shake doesn't provide at least 30 grams of protein, and if they don't consume it within 20 minutes of their last set, they will shrivel up into a skeleton, and their workout will have been a total waste.
Consuming enough protein is important, but a problem I often come across is people lacking the understanding of, and not implementing post workout carbohydrates correctly.
After a typical training session, my post workout "meal" is exactly this....
1 banana and 16oz. low-fat chocolate milk.
The macronutrient profile of this meal...
79 grams carbohydrate
5 grams fat
17 grams protein
If your goal is to put on as much muscle mass as humanly possible, your post workout meal will be different than this.
But keep in mind that my goals are simply to be strong and healthy, stay relatively lean, and maintain some muscle mass. Basically to look somewhat fit and athletic.
When someone asks me what they should eat or drink after a workout, I typically recommend they consume something that is in the range of a 2 to 1, all the way up to a 4 to 1, carb to protein ratio. My banana and chocolate milk actually puts me closer to a 5:1 ratio. I also prefer consuming something closer to a whole food source, and further away from a highly processed protein powder.
With my banana and chocolate milk, I am working with only 17 grams of protein. To some of you, that doesn't seem like enough. But I have found this quantity to work well for the goals I have, and I have yet to shrivel into a skeleton. (It is worth noting that after some training sessions, I don't consume anything, intentionally).
The reason I like such a high amount of carbs is to provide an insulin spike.
Insulin is your body's most powerful storage hormone. When there is too much sugar (glucose) in your blood, some of that sugar needs to be cleared out. Insulin is what takes care of that. It shuttles some of the glucose out of the bloodstream and into cells that can house it (fat cells or muscle cells). When glucose enters muscle cells, it becomes glycogen, simply stored carbohydrate.
When you work out, your body uses glycogen as an energy source. When glycogen gets used up, your muscle cells empty. When muscle cells are emptied, they can be refilled with glucose brought from the bloodstream (to be stored as glycogen inside the cell). This is why your body is very "absorptive" immediately after training - your muscle cells easily take in the surplus of glucose and nutrients from the bloodstream.
Having well replenished glycogen levels is what will cease muscle breakdown, allow you to recover from your training session, and most importantly, prepare you for your next workout.
When it comes to post workout nutrition, I am more interested in replenishing glycogen stores than I am with protein quantity and timing. You can get enough protein throughout the course of the day. But the best time to get a surge of carbs (that will end up being sent directly to muscle cells, and not fat cells) is during the post workout window.
I can go into greater detail on this. I'll leave it here for now. If you want me to elaborate on this, let me know....