Are you getting enough of this sneaky amino acid that makes helps repair muscles after a workout?

By Caitlin Carlson
February 23, 2015
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What you eat after your workout is almost as important as doing the workout in the first place. And you probably know that, whether it's a snack or meal, your repast should include some protein, since it's the nutrient that helps repair your hard-worked muscles. (Find out Why Women Need a New Approach to Sports Nutrition.)

But even if this isn't news to you-and you have a handful of protein-rich options at the ready at all times-here's what you may not know: All protein sources aren't created equal. Different protein foods are made up of more or less of 20 important amino acids (the building blocks of protein), one of which we're most interested in right now. (Check out Ask the Diet Doctor: Essential Amino Acids.)

"Leucine is one of many amino acids and as research evolves more studies show the unique role it plays in muscle protein synthesis," explains Connie Diekman, R.D., director of university nutrition at Washington University in St Louis.

Muscle protein synthesis is what happens when your body builds or rebuilds new proteins that are stronger than their previous versions. And a new study in Medicine & Science in Sports & Exercise found that getting five grams of leucine acid post-workout within a snack that has 23 grams of protein may be the sweet spot when it comes to getting this muscle-building benefit. Study participants who took down a nosh with 23 grams of protein and 5 grams of leucine had a 33 percent higher rate of muscle protein synthesis compared to study participants who had a snack packed with just carbs and fat. What's more, those who had triple the amount of protein and leucine had "negligible" differences in benefits, so it turns out that more isn't necessarily better.

Conveniently, many protein sources already include leucine. Diekman recommends soybeans, peanuts, salmon, almonds, chicken, eggs, and oats. "While leucine is found in most animal protein foods these particular ones provide greater amounts, making it easier for women to boost intake at all times and after a workout," says Diekman. (See: The Best Way to Gain Lean Muscle.)

Make your munchie even more powerful by adding some carbs: "Consuming leucine with carbohydrates like whole grains, fruit, and vegetables probably provides more stimulation of the muscle building pathways resulting in better after exercise recovery," says Diekman. Try a couple hard boiled eggs with whole grain toast and peanut butter or salmon with brown rice and broccoli.

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