The role and differences between types of protein is a somewhat complicated section of performance nutrition, but it doesn’t have to be super complicated. Protein intake in the pre and post workout phase can help to aid recovery and minimize muscle breakdown. Prophylactic intake of protein in the pre-workout phase will provide free amino acids in the blood stream to help buffer the catabolic effect of physical activity on muscle. In the context of the post workout phase, the role of protein is to help the body recovery from and adapt to the specific stress applied.
Soy protein is generally better reserved for pre and during workout/activity consumption. This is due to its amino acid profile which has higher levels of the three main amino acids hit during activity (leucine, isoleucine and valine), and the lack of a metabolic ammonia by-product during activity. Ammonia has been linked to increased muscular fatigue and it also forces the kidneys to work overtime to remove the ammonia from the circulatory system. Approximately 16 oz of soy milk is a good amount to intake an hour or so before a hard workout, especially if that workout goes into the endurance timeframe (> 90 minutes).
In essentially all cases, whey protein is the preferred type of protein supplement to use for recovery. This is due to whey protein’s ability to be easily processed by the body (bio-availability) and its more complete amino acid profile and how that relates to how completely the body utilizes the protein (biological value). When discussing whey protein powders there are generally two options; whey protein concentrate and whey protein isolate. Whey protein concentrate is the less pure form of whey protein, being at most less than 90% pure (generally far less) with the rest being fillers (carbohydrates, principally lactose, and fats). Whey protein isolate is at least 90% pure with very little fat or lactose. Whey protein isolate is more expensive than whey protein concentrate but generally is a better choice for recovery or protein supplement.
After physical activity, there is a 30 minute “window” for recovery in which the body is primed to intake carbohydrates and protein and restore muscle/liver glycogen stores and engage protein synthesis (muscle recovery) respectively. Ideally, a 3:1 ratio of carbohydrate to protein is considered to be the most effective combination to maximize recovery from a workout. You can find pre-mixed powders that conform to this ratio (Hammer Recoverite being one example, and the one I use). Pre-mixed powders will be at a premium price though, 32 servings of Recoverite runs about $50. Alternatively, chocolate milk makes a great substitute for the expensive powders; a sort of poor man’s recovery drink. The important thing to check with chocolate milk is that high fructose corn syrup is not used as the sweetener. Try to find the chocolate milk with the shortest, most natural ingredient list and watching the fat levels won’t hurt either. Ideally you want your recovery mix to be minimal calories, minimal filler, and maximum nutritional benefit (3:1 carbohydrate to protein ratio).
In the end, anything will be better than nothing. Depending on your activity level and objectives, you’ll have to supplement with additional protein intake outside of the post-workout period. This is where protein shakes come in handy. However, consuming straight protein isolate with no additional sugar before bed anecdotally has been linked to increased levels of human growth hormone and elevated immuno response. If training hard, consider pre-workout nutrition as important as post-workout nutrition to minimize muscle breakdown. You should notice how when you get recovery right, it will allow you to push harder and feel better the next day. Just remember that your body has limits and remember to listen to them.