The Leeds Beckett team gave the supplements to a cohort of elderly people over a three month period, and tested them both before and afterwards to assess whether their physical fitness and strength had improved.
Some of the participants took supplements containing the amino acids, while others took a placebo. The researchers found significant improvements among the volunteers taking the amino acid supplement.
Amino acids are important because they are the building blocks of proteins which are responsible for building muscle tissue. Many of these amino acids are not made by our bodies, but supplied through the food we eat.
For elderly people, however, maintaining muscle mass becomes problematic. From the age of 65 onwards it starts to decrease at greater rates, leading naturally to a loss of physical strength and increased frailty. This can cause falls, fractures and other disabilities, affecting independence and, as our aging population expands, placing a growing burden on health and care services.
Increasing the amount of protein in the diet would help, but high protein diets make people feel fuller, so they are less likely to be able to get enough of the other nutrients and energy that they need from food,
The Leeds Beckett researchers, based in the University’s School of Sport in the Carnegie Faculty, examined whether essential amino acids could be added instead to the diets of elderly people to improve muscle mass. The supplements were given, in capsule form, to a cohort of 25 people aged between 65 and 75. Sixteen people received a supplement that included differing concentrations of Leucine, an important amino acid which is popular among body builders as it is known to boost the body’s ability to make muscle from protein. The overall amount of supplement each person was given was based on their body weight. The remaining nine people took a placebo capsule.
Each member of the cohort was tested at the start of the trial with a series of simple physical and body composition tests, including a handgrip test, a six-minute walk test to assess aerobic capacity, and a 30-second chair stand test to assess their muscle mass and the function of their muscles. After three months of taking the supplement, they were tested again to see if these had improved. The results, published in this month’s European Journal of Clinical Nutrition, showed clear evidence of performance improvements in both amino acid groups whilst the group taking supplements containing higher levels of Leucine also showed gains of more than 1 per cent in muscle mass.
“The improvements we measured in people taking these higher levels of Leucine clearly show that amino acid supplements have real potential for improving the physical condition of elderly people,” says Dr Theocharis Ispoglou, who led the study. “This could be useful among the healthy elderly population, to help them meet their daily energy needs, or it could be useful in the clinic, to help frail elderly people regain some physical fitness.”
The researchers also reported that the study subjects found it difficult to take the full dose of supplement, which required up to 30 capsules to be taken over the course of a day. Dr Ispoglou and his team have developed more palatable forms of the supplement that allow higher concentrations to be delivered via flavoured gels or bars. A larger study, which included these new products, has recently been completed and preliminary analysis of data has shown clear benefits in relation to appetite and palatability for both the gel and the bar.
“This opens up exciting new opportunities where these supplements can potentially assist elderly people to meet their energy and protein needs, and ultimately lead a healthier and independent lifestyle for as long as possible,” adds Dr Ispoglou.