As bodybuilder and trainer Nick Nilsson explains, weight training itself doesn't spur muscle growth, it actually causes muscle damage. This damage must be repaired for growth to occur, and the primary way in which damage is repaired is by supplying nutrients to your muscles by consuming food. Consuming food after your workout is the best way to promote growth, although the nutrients you consume do make a difference.
Post-Workout Meal Timing
Although the suggestion that you need to consume nutrients within one hour of your workout is a common one, bodybuilder Dave Barr notes that research indicates that this recommendation is inaccurate. Barr explains that your body's enhanced receptiveness to nutrients lasts at least 24 hours, and that immediately consuming protein after a workout can hinder progress. Based on these facts, consuming your post-workout meal between one and 24 hours after exercise appears ideal. Beginning your feeding sooner rather than later can be beneficial, as it gives you more time to consume more calories, and a calorie surplus is required for muscle gain.
Protein is a vital nutrient to consume for muscle gain and workout recovery, as it provides the amino acids your body uses for muscle building. Nutrition researcher Dr. John Berardi explains that protein is especially important for post-workout meals, as it helps reverse the muscle breakdown caused by exercise. Protein consumption also triggers protein synthesis, which spurs muscle growth. Dr. Berardi advocates consuming .4 g of protein per kilogram of body weight after exercise.
Carbohydrates might help promote exercise recovery, as they can restore muscle glycogen, the energy stored in your muscles that is used up during workouts. In addition, Dr. Berardi notes that combining carbohydrates with protein can aid in muscle repair. Dr. Berardi suggests consuming .8 g of protein per kilogram of body weight in your post-workout meal.
Consuming fat can be helpful for building muscle, so you might want to include some in your post-workout meal. Research from the October 2003 issue of the journal "Gut" indicates that adding omega-3 fatty acids -- fond in salmon, olive oil and other foods -- to protein supplements increases the amount of muscle such supplements can build.