Muscle Strength and Physical Performance in Relation to Dietary Intake Among Older Men and Women

Background: The aim of this study was to examine the relationships between dietary intake and two key components of sarcopenia in older, sex- and age-matched men and women: muscle strength and physical performance. Methods: The study included 620 carefully selected community-dwelling adults aged 60 years and more (310 men and 310 women) matched by sex and age (±1 year; median age: 66 years). Body mass and body mass index were assessed. Dietary intake was evaluated using 24 h dietary recall questionnaire and analyzed with Dieta 5.0 software. Handgrip strength (HGS) was measured using a hydraulic hand dynamometer, while physical performance using the Timed Up and Go test (TUG). Results: In men, but not in women, higher intakes of multiple dietary components, especially proteins, were associated with greater HGS. TUG was inversely related to animal protein, some amino acids, folate and vitamin C in men, whereas in women to copper, magnesium, vitamins C and E, riboflavin, and PUFA intakes. After multivariable adjustment, no nutrient remained associated with HGS in both sexes. In women, vitamin C intake remained inversely associated with TUG. Age was the strongest predictor of HGS, while age, physical activity (PA) and chronic diseases were significant factors associated with TUG in both sexes. Conclusions: Our findings show multifactorial nature of muscle physiology, suggesting that in preventive strategies adequate dietary intake integrated with PA and effective management of chronic diseases is required, as nutrition alone appears insufficient to preserve muscle function. The sex-stratified associations suggest that personalized dietary recommendations may be beneficial.