Combining the amino acids L-Theanine with Cystine helps protect athletes from infection

January 06, 2010

     Athletes become increasingly susceptible to infection during training because their immune system becomes suppressed. Researchers at the Department of Sports Science, Juntendo University, Japan investigated the health of the immune system in fifteen long-distance runners after supplementing them with the amino acid Cystine combined with L-Theanine (CT). The amino acids have been reported to have an immune reinforcement effect. The athletes were supplemented or given placebo (sham treatment) for ten days prior to training that involved a prolonged period of intense exercise. Clinical examinations were performed before and after the training.
     The results indicate a significant increase in the level of high-sensitivity C-reactive protein or hs-CRP which is a proxy for showing that there is rising inflammation. The neutrophil count in the blood also rose while there was a tendency for a drop in the number of lymphocytes in the placebo group, but not in the the CT group. These observations suggest that the ingestion of CT contributed to suppressing the response leading to a rise in inflammation and prevented a decrease in immune function associated with continuous intense exercise. The study is published online ahead of print in the journal Bioscience, Biotechnology, and Biochemistry.