Serious teen athletes and exercise enthusiasts are often seeking new ways to gain a competitive edge or to improve exercise performance. The allure of using supplements to enhance athletic performance is especially appealing to this age group, particularly when slick advertising campaigns target the youth market. Energy drinks containing amino acids like L-arginine are often used by teens. But concerns about safety have led scientists to caution against their use.
L-arginine, often called simply arginine, is an amino acid that is naturally produced by your body and contained in many foods. Amino acids are proteins that your body uses to build and repair tissue and assist in many metabolic functions. In your body, arginine breaks down to nitric oxide, a chemical that plays an active role in circulation and muscle growth and function. According to the Mayo Clinic, arginine triggers the body to make protein and may improve wound healing, muscle hypertrophy and sperm production as well as prevent muscle wasting in the critically ill.
L-Arginine and Athletic Performance
Because of its muscle-building properties, arginine is an ingredient in many bodybuilding supplements. Yet there is little evidence to support its potential for improving athletic performance. Sports scientist Dr. Rob Wood of Top End Sports notes that under some circumstances your body may need more amino acids than normal. Those circumstances include periods of rapid growth as in the teen years, while engaged in a resistance training program and for tissue repair after an injury or illness. Dr. Wood cites evidence that arginine, along with the amino acids lysine and orthinine, may stimulate growth hormone in children and teens. However, he advocates an increase in dietary protein and discourages supplementation for teenage athletes.
L-Arginine in Energy Drinks
L-arginine and other amino acids are often added to energy drinks, causing them to be classified as dietary supplements and therefore beyond the reach of the FDA, which regulates the amount of caffeine contained in soft drinks. A study published in the February 2011 issue of "Pediatrics" called for physicians to heighten their awareness of young patients who use energy drinks, especially athletes and children with ADHD, diabetes and eating disorders. High school athletic trainer David Edell challenges the safety and effectiveness of energy drinks for young athletes. Edell points to high concentrations of sugar and caffeine that can lead to dehydration and impede athletic performance. He argues that the effectiveness of amino acids like arginine added to energy drinks to enhance performance lacks scientific support.
To increase arginine levels, Dr. Rob Wood recommends teen athletes increase their total energy intake from foods, especially those that naturally contain high levels of amino acids. Lean meats, chicken, fish, dairy, eggs and legumes are all good sources. The Mayo Clinic lists nuts, seeds, whole grains and chocolate as good dietary sources of L-arginine. Watermelon is high in the amino acid L-citruline, from which your body makes L-arginine.