There was a recent study published by the Gatorade Sports Science Institute about consuming a carbohydrate electrolyte enhanced beverage (CEB) during and after a workout and what impact it has on recovery and subsequent performance. It also addressed the benefits if any on consuming amino acids and protein during a workout.
Finally it discusses post workout consumption of protein with carbohydrates and if they aid the body and help with subsequent performance.
The facts on Pre and Post Consumption and your workout
Does consumption during your workout give you a boost?
The consensus of the study from a science perspective is consuming amino acids and protein during a workout show no benefit to performance than consuming just a CEB. After you finish your workout adding a protein to carbohydrate consumption did not aid in subsequent performance. Just eating carbohydrates was acceptable to the body for fuel and replenishing glycogen as long as enough was consumed. It did note that adding protein is valuable for muscle repair and recovery but there was no difference in performance.
We hear all the time what you should or shouldn't put in your body, who is right?
Whether you agree or disagree you can look at what science has to say then test it out for yourself and find the best mix for you. The take home is keep it simple. Fuel your body with energy before you work out. During activity consume plenty of electrolyte infused beverages and when finished be sure to eat plenty of carbohydrates.
The muscles need the sugar to replenish themselves. If you want to learn more read about the glycemic index. It is fascinating stuff. Enjoy your next workout and make sure you fuel your body properly. You don't need to buy all kinds of fancy stuff from the health food store. Just make sure you stay hydrated and be smart with your protein and carbohydrate consumption if you want to achieve your best level of performance.