When performing a resistance training workout, your body is stretching and tearing muscle fibers. This may seem like a bad thing, but make no mistake, it's the process by which your muscles initiate hypertrophy (growth). One of the most vital steps involved in making this happen is feeding your muscles what they need right after your workout. And by right after, I mean RIGHT after.

For the most part, you have a window of about 30 minutes after your weightlifting workout to eat your post-workout meal, or else your body may become catabolic (a situation where you actually lose muscle).

Does what you eat matter? Absolutely. Unlike any other part of the day, you need some simple, fast-digesting carbs right after a resistance training routine. Think white bread with a Tbsp of jelly or a bottle of Gatorade. This is because your body requires immediate sustenance in order to begin rebuilding. Also, it is equally important that you consume an adequate amount of protein right after a weight workout -- preferably whey, as it digests faster than casein protein. As a matter of fact, a great post-workout drink is low-fat chocolate milk, for it contains a good amount of protein, high amounts of simple sugar, and only a minimal amount of fat.

One thing you do want to avoid right after a weight training workout is fat of any kind. Although nuts, avocados, olive oil and flax seed oil and other healthy fats should be part of your daily diet, they should not be consumed during your post-weight workout meal. Fats slow the absorption of carbohydrates and protein, which works against your goal of almost instant replenishment during this post-weight workout window.