Home-based exercise and amino acid supplementation in older adults: a randomized controlled trial study

Purpose: Aging causes structural and functional changes in skeletal muscle, decreasing quality of life. This Randomized Controlled Trial study evaluated the effect of a 24-week home-based resistance training program and amino acids supplementation on physical performance and muscle health in sedentary older adults. Methods: The study was a randomized controlled trial. Thirty-five sedentary older adults (60–80 years) were randomly assigned to three groups performing: 24-week resistance exercise (EXE, n = 11), 24-week resistance exercise plus amino acids for 12 weeks (EXE + SUPPL, n = 12), and a control group (CON, n = 12). Body composition, intermuscular adipose tissue (IMAT), cross-sectional area (CSA) of thigh, appendicular–skeletal–muscle–mass index (ASMMI), strength, balance, and gait capacity (Mini-BESTest) were assessed at the beginning (T0) and after 24 weeks (T1). Results: At T1, > 15% improvement in the Chair-Stand-Test was achieved by 82% of EXE, 67% of EXE + SUPPL, and 25% of CON participants. In addition, chi-square test showed significant differences between EXE versus CON (p = 0.006) and EXE + SUPPL versus CON (p = 0.041) in Chair-Stand-Test evaluation. Muscle mass of lower limbs (p = 0.005) and ASMMI (p = 0.010) decreased in the CON group. EXE participants showed greater increases in upper limb muscle mass than CON (p = 0.042). Improvements were observed in the Chair-Stand-Test (EXE and EXE + SUPPL, p = 0.001), handgrip test (EXE + SUPPL, p = 0.002), and One-Repetition-Maximum (EXE + SUPPL, p = 0.022). EXE + SUPPL had greater handgrip test improvements than EXE (p = 0.023). Conclusions: Data demonstrated that home-based exercise could be an alternative method from traditional training practices, as it increases submaximal strength of the lower limbs and conserves muscle mass in older adults.