How much protein you’ll need after your workout depends on your body weight. The International Society of Sports Nutrition article suggests 0.25 to 0.40 grams of protein for each kilogram of body weight. If you weigh 150 pounds, that’s 17 to 27 grams of protein to stimulate muscle protein synthesis.
While a hard muscle-building workout requires protein for muscle synthesis, you’ll also need to add some carbs to help your body absorb protein and replenish lost muscle glycogen. Your body will need 0.8 grams of carbohydrates for each kilogram of body weight, which is about 54 grams of carbs for someone weighing 150 pounds.
You can easily reach these goals with a blueberry banana smoothie. A cup of blueberries, a medium banana, and a scoop of whey protein give you 51 grams of carbohydrates and 26 grams of protein (depending on your brand of protein powder). According to a 2013 article in the Nestle Nutrition Institute Workshop Series, whey protein is best after a workout because it’s absorbed by your body more rapidly to get to work on building that muscle.