Since muscle tissue is indeed composed of mostly protein and water, it seems only natural to consume protein throughout the day. However, there are KEY time periods in which you can get the best "bang for your buck" from a protein shake or supplement. GNC sells 20 g/serving powders with over 70 servings for only around 20$ (this should last you a while). Here are the best times to consume a protein shake:
1) BEFORE A CARDIO WORKOUT- The reason for this lies in the fact that protein protects the muscle from being burned for energy. It would be best to consume the shake (or eat the bar) at leat 20-30 minutes before the workout (this is the amount of time it takes for Whey protein, on average, to be digested and reach the muscle)
2) DIRECTLY FOLLOWING A RESISTANCE TRAINING WORKOUT- The reason for this is that the first hour to 2 hours following a weight training session is a critical time period for muscle reperation. You want to feed the muscle some protein (and plenty of water, but I will touch on this later) directly following the workout.
3) RIGHT BEFORE YOU GO TO SLEEP-While you are sleeping your muscles repair themselves. This is why it is extremely important that you get your full 8 hours of sleep each evening. Feeding the muscle protein before bed will help with the process of reperation. You are also avoiding the chance of actually burning off your protein while you are sleeping because your body is at rest and burning few calories.
I do suggest getting some sort of protein shake or bar. Whey protein is the fastest acting protein. If you are trying to build muscle, lose fat, or whatever the case may be, it is good to consume at least 1g of protein per 1lb of body weight. If you weigh 175 lbs, then you are required to consume 175 grams of protein a day. It is rather difficult to actually consume this much without a protein shake or bar. I'm not saying it cannot be done, but it is much easier if you have some help from a supplement.
---WATER---
You need to consume around half your body weight in ounces of water each day. Eg. 180 lbs is required to drink around 90 ounces of water each day. Muscle tissue (and the body for that matter) is composed of water mostly. Dehydration causes fatigue, strength loss, and many other things. Water also helps digest the protein shake.
Think of it like this, muscle is composed of water and protein for the most part...so FEED YOUR BODY WHAT IT IS MADE OF!
When going to purchase your shake I warn you that these people at supplement stores are going to want to sell you anything that is the most expensive, or simply as much they can push over on you. You only need a shake that has around 20-25g/serving. There are more expensive powders that contain around 50 g/serving. The 50 may sound better, but in actuality it is not. The muscle will only recieve around 25 g, and the rest will go to your kidney and other places, so it is actually a waste of money.
scott