The time to exhaustion was significantly longer during for both low and high doses of Sustamine, compared with no hydration, according to findings published in the Journal of American College of Nutrition. There was no difference between a sports drink and no hydration, added researchers from the University of Central Florida.
“Ingestion of Sustamine [the alanine-glutamine dipeptide] at either the low- or high-dose significantly improved time to exhaustion during high-intensity exercise compared to a no-hydration trial,” said Dr. Jay Hoffman, one of the study scientists and UCF Department of Sport and Exercise Science professor.
“For endurance athletes such as long-distance runners, the addition of Sustamine in hydration protocols may allow for longer times before exhaustion sets in.”
Sustamine has continued to gain traction in the US sports nutrition marketplace, with Kyowa Hakko’s fermentation technology delivering glutamine via a dipeptide, which solves the stability issue of this notoriously unstable amino acid. The dipeptide form may also offer some other distinct benefits such as enhanced recovery, immune system support, and increased metabolic rate, according to Kyowa.
Research also suggests that Sustamine is absorbed more than 200% better than standard L-glutamine (Harris et al. Nutr Res, 2012, Vol. 32, pp. 272-7), which means better results at a lower dose.
The UCF researchers recruited 12 male endurance athletes and got them to perform four endurance trials – each consisting of one-hour treadmill runs at 75% VO2 peak followed by a run to exhaustion at 90% VO2 peak. One trial allowed no hydration; the second used a commercial sports drink (1L), while the other two trials involved the sports beverages supplemented with 600 mg/L or 2g/L of Sustamine. Participants drank 250ml every 15 minutes.
Results showed that the time to exhaustion was significantly longer during in both Sustamine trials compared to no hydration. There was no difference in time to exhaustion between sports drink only and no hydration.
In addition, plasma glutamine concentrations were significantly elevated at 45-minutes in the Sustamine trials, and remained elevated at 60 minutes during the high-dose test.
Sodium concentrations increased from the beginning of exercise and remained stable for the duration of the one-hour run. At 60 minutes, plasma sodium was significantly lower in all trials compared with no hydration.
“Results indicated that ingestion of the alanine-glutamine dipeptide at either the low or high dose significantly improved time to exhaustion during high-intensity exercise compared to a no-hydration trial,” concluded the researchers.
Source: Journal of American College of Nutrition
Published online ahead of print, doi: 10.1080/07315724.2015.1009193
“Effects of l-Alanyl-l-Glutamine Ingestion on One-Hour Run Performance”
Authors: W.P. McCormack, J.R. Hoffman, G.J. Pruna, et al.