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Background: Ageing is a natural, progressive and irreversible process characterized by morphological, psychological, functional, biochemical and nutritional changes. Physical inactivity (PI) is a factor that contributes to the starting of mass and muscle function decline in the elderly, often related to sarcopenia and physical frailty. Combined to protein nutritional intervention, exercise appears as an effective way to prevent muscle mass and physical fitness decline. In addition, the elderly population has difficulty in maintaining adequate protein nutrition and are the least involved in systematic exercise programs. This exploratory study was conducted to understand the isolated and combined effects of a 16-weeks of branched chain aminoacids (BCAA) supplementation (BS) and muscle strength exercise program (MSE) on functional-fitness performance in octogenarians. Methods: The sample consisted of 18 participants aged 82.97±8.05 years old, institutionalized in social care centres. They were divided into two groups: group 1 (MSE+BS, n=10); group 2 (BS, n= 8). Group 1 performed an elastic band strength exercise program carried out during 16-weeks together with BCAA supplementation consisting of ingesting 0.21g/kg/day of unflavoured powder diluted into 200mls of water, immediately after exercise. Group 1 did only the BCAA supplementation. To evaluate the functional capacity of the elderly, the short battery of tests SPPB was used in the initial and final intervention evaluation. Results: After 16 weeks, group 1 (MSE+BS) showed a significant increase in all the SPPB tests performance, particularly in the test consisting in rising from a chair and seating down for 5 times. The SB group showed only a short decrease in the time taken to perform the 3 meters walk test (p < .05). Conclusion: Our study revealed that exercise plus supplementation with BCAAs was able to improve physical fitness function, while BCAA supplementation alone had limited effects. Satisfactory results in physical function could be explained by the added effects of exercise and BCAA supplementation on the protein synthesis effect.

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Protein and amino acid requirements in human nutrition
WHO/FAO/UNU Expert Consultation. (2007). Protein and amino acid requirements in human nutrition. World Health Organization Technical Report Series, (935), 1-265. https://doi.org/ISBN 92 4 120935 6