Sustamine Boosts Sports Performance

NEW YORKA clinical study by Jay Hoffman, Ph.D., professor and chair of the Department of Health and Exercise Science at the College of New Jersey, showed Sustamine L-Alanyl-L-Glutamine (AG; from Kyowa Hakko Bio Co. Ltd.), an amino acid dipeptide, increased performance in endurance exercise and activity (J Inter Soci Sports Nutr. 2010; DOI:10.1186/1550-2783-7-8).

Ten physically active males volunteered to participate in the study. During the first visit (T1), subjects reported to the laboratory in a euhydrated state to provide a baseline (BL) blood draw and perform a maximal exercise test. In the four subsequent randomly ordered trials, subjects dehydrated to -2.5 percent of their baseline body mass. For T2, subjects achieved their goal weight and were not rehydrated. During T3 to T5, subjects reached their goal weight and then rehydrated to 1.5 percent of their baseline body mass by drinking either water (T3) or two different doses (T4 and T5) of the AG supplement. Subjects then exercised at a workload that elicited 75 percent of their VO2 max on a cycle ergometer. During T2 to T5 blood draws occurred once goal body mass was achieved (DHY), immediately prior to the exercise stress (RHY) and immediately following the exercise protocol (IP).

Glutamine concentrations for T5 were significantly higher at RHY and IP than T2 to T4. When examining performance changes, significantly greater times to exhaustion occurred during T4 and T5 compared to T2. Plasma sodium concentrations were greater (P<0.05) at RHY and IP for T2 than all other trials. Aldosterone concentrations at RHY and IP were significantly lower than that at BL and DHY. AVP was significantly elevated at DHY, RHY and IP compared to BL measures. No significant differences were observed between trials in C-reactive protein (CRP), IL-6, malondialdehyde (MDA) or in any of the other hormonal or biochemical measures. The results demonstrated AG supplementation provided a significant ergogenic benefit by increasing time to exhaustion during a mild hydration stress. This ergogenic effect was likely mediated by an enhanced fluid and electrolyte uptake.