Natural amino acid leucine may help burn fat and keep muscle tissue strong during intense exercise

Monday, August 29, 2011 by: S. L. Baker, features writer
Tags: leucine, extreme exercise, health news

(NaturalNews) Researchers studying some of the toughest exercisers around -- folks who climb the highest peak on Earth, Mt. Everest -- have come up with evidence that the amino acid leucine may help people burn fat during times when they can't eat (such as mountain climbing) while keeping their muscle tissues strong. The new data was just reported at the 242nd National Meeting and Exposition of the American Chemical Society (ACS), currently being held in Denver.

In a pilot study, scientists supplemented the diet of an elite group of men and women mountain climbers with the amino acid leucine, a natural substance found in many foods (including lentils, peanuts, almonds, eggs and flax seeds), dietary supplements, and some energy bars.

In all, the researchers studied 10 climbers for 6 to 8 weeks as they ascended Mt. Everest, which towers 29,000 feet above sea level. They measured the physiological benefits of adding leucine to the climbers diets to see if the amino acid would help the climbers stay healthier and stronger on their trek -- and it appeared to do just that.

Wayne Askew, Ph.D., and his co-investigator, Stacie Wing-Gaia, Ph.D., of the University of Utah, who headed the leucine study, explained in a statement to the media that the extreme weather conditions, low oxygen levels, treacherous terrain and strenuous exercise during such mountain climbs place an enormous nutritional challenge on the bodies of climbers.

For example, weight loss at high altitudes is a problem because climbers often cannot or do not eat enough calories as they climb, so they are unable to replenish their bodies with important nutrients. This results in the loss of both fat and muscle -- and that can cause mountain climbers to become weak and lose motor coordination. At high altitudes, fat and muscle loss occurs at rest, too, and not just during arduous climbing.

"The significant part about this weight loss is that a disproportionate amount comes from the muscle mass," Dr. Askew said in a statement to the media. "This can be a problem on long expeditions at high altitude because the longer climbers are there and the higher they go, the weaker they get. The body breaks down the muscle for energy, so climbers don't have it available for moving up the mountain."

"We knew that leucine has been shown to help people on very low-calorie, or so-called calorie-restricted diets, stay healthy at sea level," he added. "It's one of the components, the building blocks, of protein. But no one had tested whether leucine would help people stay healthy and strong at high altitudes, so we added leucine to specially prepared food bars that we gave to the climbers."

For their study, members of Dr. Askew's research team, Dr. Wing-Gaia and Dr. Rodway, went to the climbers base camp and used an ultrasound device to measure the expedition members fat and muscle. They are currently studying the data they collected to see whether the climbers who ate leucine containing bars retained more muscle than those who ate energy bars without leucine -- so far, it appears they did.

One early finding in the study was that the way leucine was delivered was critically important. The Everest climbers found it hard to eat three food bars per day that contained the additional leucine. While the current research was promising and suggests leucine may keep muscles strong during hard exercise, Dr. Askew added that a more controlled clinical study is needed along with improvements in easier-to-eat leucine food.

To this end, the researchers are consulting with military food product developers at Natick Research Development and Engineering Center and plan to conduct a more controlled study at high altitudes, possibly with the U.S. Army Institute of Environmental Medicine at their laboratory on Pike's Peak.

Dr. Askew pointed out that the findings about leucine's benefits aren't just good news for elite mountain climbers --they could also could help many people at low altitudes who simply want to lose weight while preserving their lean body mass. Leucine may be of particular benefit to the elders who want to maintain stronger muscles, too.

For more information
http://portal.acs.org/portal/acs/corg/conten...