Leucine is an essential amino acid used in the liver, fat tissue, and muscle tissue.It is one of the branched-chain amino acids (BCAA) that make up about one-third of muscle protein.1 It is also suspected to be the only amino acid which can stimulate muscle growth, and can also help prevent the deterioration of muscle with age.2
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Is leucine tied to improved sports performance? The answer is yes according to Jenna A. Bell PhD, RD, (I know Jenna~she is amazing!!!)
“Adequate protein intake is critical for athletic performance and good health. There is increasing agreement that immediate post-exercise ingestion of protein, specifically leucine, combined with carbohydrate, has beneficial effects on:
- muscle glycogen replenishment (carbohydrate) and
- muscle protein synthesis (leucine)
Protein intake helps promote muscle recovery and eventual hypertrophy” (enlargement by cell growth).
Jenna makes a point that the type of protein and the timing is most important.
Foods high in leucine include cheese, soybeans, beef, chicken, pork, nuts, seeds, fish, seafood, and beans. 3 However, many athletes want to boost their intake of BCAA and leucine in particular, so they turn to supplements. When it comes to supplements, whey protein is highest in leucine with soy coming in a close second.
Timing seems to be an important variable when it comes to supplementation. I found some literature to report immediately post-exercise and some gives a three hour window. Immediately seems to be the more pronounced report.
Now, back to where we began…Leucine as a supplement? Taken responsibly, the literature (mostly) agrees that 2.0 grams (either taken as food or a supplement) is considered safe for healthy adults and 2.5 grams for athletes to stimulate muscle protein synthesis and recovery.
So, there we have it! More than you needed to know? Oops! Want to know more? Great!
Next week~Chia Seeds: another Super Foods for athletes!