Protein after weight lifting is important: it helps repair muscle damage and help build new muscle. Timing is important as well. After exercise, the body is more sensitive to insulin, a hormone that helps shuttle amino acids (the building blocks of protein) and glucose into muscle cells. We have a 45 minute window of opportunity, but the first 15-20 minutes are ideal.
Athletes have a greater need because of greater lean mass, greater need for tissue repair, and some modest amounts of protein used as energy. Strength athletes do need more than an endurance athlete (1.6-1.7g/kg per day compared to 1.2-1.4g/kg per day) and definitely needs more than the average joe (0.8g/kg per day), but meeting those elevated needs is rarely a problem for strength athletes. Strength athletes often consume multiple servings of protein powders and supplements thinking this can aid in muscle gain.
In actuality, only 1.5g of additional protein is needed for every kilogram of muscle mass desired. An additional 30g carbohydrates/kg desired is required for energy. If not enough carbs are consumed, protein is used for energy instead of muscle building. This breaks down into 4.5g additional protein for a 6.6lb muscle gain; that’s less than the amount of protein in one large egg and the number of carbs in a piece of toast.
Most protein powders have 25-30 grams per scoop and packages encourage 2 scoops multiple times per day. Extra calories, including calories from protein, is used for energy or stored as fat. Using protein for energy is not only inefficient but creates an extra tax on the kidneys to filter the protein waste product, nitrogen. This can even lead to dehydration. Most studies comparing the effects of protein powders on weight gain conclude that they may help but mostly in the role of accomplishing sufficient calories for muscle gain. Therefore, less expensive sources of protein such as eggs, beans, tuna, quinoa, etc., are just as if not more effective.
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