WEDNESDAY, Nov. 19 (HealthDay News) -- The dietary supplement beta-alanine (BA) -- widely used by athletes and body builders -- improves muscle endurance in the elderly, according to U.S. researchers.

The finding "could have importance in the prevention of falls, and the maintenance of health and independent living in elderly men and women," said study author Jeffrey Stout of the University of Oklahoma.

BA is an amino acid that helps form carnosine, which plays a major role in normal muscle function during intense exercise. The more BA, the higher carnosine levels in muscles, the researchers said.

In this study, Stout and his colleagues assessed the fitness levels of 26 elderly men and women before and after they took BA supplements or placebo pills for 90 days.

They found a 67 percent improvement in the fitness levels of those who took BA, compared to a 21.5 percent improvement in the placebo group.

"Our data suggest that 90 days of BA supplementation increased physical working capacity in elderly men and women," the study authors wrote. "These findings are clinically significant, as a decrease in functional capacity to perform daily living tasks has been associated with an increase in mortality, primarily due to increased risk of falls."

The study was published online this month in the Journal of the International Society of Sports Nutrition.

More information

The U.S. National Institute on Aging has more about falls and older adults.