Nutrition assistance improves skeletal muscle function and performance in community-dwelling older women

Objective: To analyze the effects of nutritional assistance focusing on protein intake (in the individual's usual diet) in relation to muscle mass, and the muscle strength and functional performance of community-dwelling older women. Methods: This is a non-randomized controlled clinical trial. Forty-three community-dwelling older women, who were allocated to the Control Group (CG; n = 20) or the Nutrition Group (NG; n = 23). The NG received individualized nutrition assistance and participated in group activities that focused on dietary protein intake once a week for 12 weeks. Main outcome measures: protein and energy intake; handgrip strength (HGS); gait speed (GS); quadriceps cross-sectional area (CSA); and intramuscular non-contractile tissue (IMNCT). The Student's t-test for independent samples, the Mann-Whitney U test, and a mixed model ANOVA with two factors (group and time) were adopted, followed by a post hoc Bonferroni test. A Spearman's correlation test was performed on tests for HGS; GS; CSA; IMNCT; age; and protein intake adjusted for weight (g/kg) (p = 0.050). Results: Participants in the NG showed higher CSA values than those in the CG (p < 0.001). NG participants also had higher HGS (p < 0.001) and GS (p = 0.037) when compared to pre-intervention. Correlations were observed between IMNCT and protein intake adjusted for weight (g/kg) (r = -0.517; p = 0.020); HGS, and CSA (r = 0.827; p = 0.000); and CSA and age (r = -0.520, p = 0.009). Conclusions: A nutrition assistance program focusing on protein intake resulted in enhanced muscle function and physical performance.