Sarcopenia is the process in which people lose muscle as they get older. American adults lose about a half pound of muscle per year during their 30s and 40s, according to NSCA Essentials of Personal Training. For people past 50 years old, one pound of muscle lost per year is more likely. The irony is that the average American also gains about 10 pounds every decade, most of which is fat. As your metabolism slows, you’ll require less energy and therefore store calories that you used in your youth as fat as you age. The combination of strength training and eating enough protein can mitigate sarcopenia.
Amino acids are the building blocks of protein– organic compounds found in muscles and tissues that serve a variety of physical functions from being an energy source during endurance training to giving human cells their shape. There are nine essential amino acids that must be consumed in the diet and three of them—leucine, isoleucine and valine—are called branched chain amino acids (BCAAs). These three amino acids have been shown to enhance protein synthesis (which results in cell growth), improve gut health, decrease inflammation, and serve as biomarkers for early detection of chronic diseases like diabetes and insulin resistance, according to a 2017 Journal of Animal Science & Biotechnology review.
Of the BCAAs, leucine has been the most researched and for good reason. This powerful amino acid plays a crucial role in making gains.
THE LATEST ON LEUCINE
We know that lifting weights builds muscle but there are several variables that affect just how much muscle you’ll build. One these factors is leucine intake. When you workout, your body repairs your muscles via protein synthesis, meaning it creates new muscle fibers resulting in a larger muscle size. Leucine increases the rate of protein synthesis so you can rebuild new muscle fibers faster. A 2016 Nutrition and Metabolism review explores exactly how this happens but basically, a protein named Sestrin2 binds with leucine which leads to the activation of another protein called mechanistic target of rapamycin complex-1 (mTORC1). Activation of mTORC1 stimulates protein synthesis.
For people ages 66+, extra leucine in the diet can help speed up the protein synthesis process which naturally slows down with age, says a Endocrinology and Metabolism study. In this study, groups of young people (about 28 years old) and older folks took an amino acid supplement with either 26% or 41% leucine. All groups increased protein synthesis rates except the elderly low leucine group.
Leucine can be found in foods with high protein content such as eggs, chicken, and fish. It’s also found in whey protein supplements and amino acids products.
ATHLETES LOSE MUSCLE TOO
You don’t need to be 70 years old to lose muscle. When athletes stop training, they lose muscle and often impair their performance. Six weeks off of training resulted in muscle loss in soccer players in one 2014 PLOS ONE study. Another PLOS ONE study found that tae kwon doe athletes who stopped training for eight weeks lost muscle among other unfavorable changes. Even endurance competitions themselves can result in muscle loss. A 2010 Asia Pacific Journal of Clinical Nutrition study saw ironman triathletes lose an average of 2.2 pounds of muscle during one triathlon.
The downfalls of extended breaks from training can be mitigated by taking BCAAs. Also, endurance athletes and elderly people can experience the positive effects of leucine. Bodybuilders and fitness enthusiasts are in a race against time during and between workouts, trying to increase the rate at which they recover and build new muscle. Supplements will help keep you one step ahead of the game so you’re always ready for action without sacrificing gains.