GALVESTON, Texas, Aug. 28 (UPI) -- Astronauts who want to keep their muscles strong during long stays in space might want to guzzle down daily supplements of amino acids, according to new research by a NASA-backed biomedical institute.
The results of a study by the National Space Biomedical Research Institute also have implications for people confined to bed, the elderly and those who are inactive.
Without activity, muscles do not make new proteins, leading to atrophy and weakness. However, a research team headed by Robert Wolfe and Arny Ferrando, both with the University of Texas Medical Branch, has found three-times daily natural supplements of amino acids -- the raw materials of proteins -- helped maintain muscle mass in volunteer subjects who spent 28 days confined to bed.
Data from the bed-rest volunteers was compared with similar data from volunteers given a placebo drink instead of the amino acid brew.
"We had essential amino acids packaged in a certain ratio that allowed us to get the most bang for the buck on muscle protein," Ferrando told United Press International in an interview Wednesday. "The early results suggest that the amino acid supplement is able to maintain protein synthesis rates and muscle mass."
During the study, volunteers stayed in bed for 28 days, getting up only briefly to use a bedside toilet when needed. They ate and bathed in bed and spent their days reading, watching television and using bedside computers.
Bed confinement has a similar effect on the body as weightlessness in space.
The team plans a follow-up study next year to determine what effect occasional exercise has on muscle mass. A study combining occasional exercise with nutritional supplements also is planned.
"Preserving muscle strength and size has become a critical issue for older adults attempting to maintain independent living and quality of life," said Scott Trappe, a scientist with Ball State University in Muncie, Ind., who has published research showing the benefits of exercising even one day a week.
Trappe and his colleagues found the skeletal muscle strength gained during a 12-week progressive resistance training program would be maintained by resistance training just one day per week.
"Based on all the clinical work I've done, I think the answer for long-term space fliers is going to be a combination of exercise, nutritional supplements and perhaps some light hormonal intervention," Ferrando added.