Sarcopenia is the main factor involved in the development of frailty syndrome. The aims here were to investigate relationships between lower-limb muscle strength and the variables of sex, age and frailty criteria; compare lower-limb muscle strength with each frailty criterion; and assess the power of each criterion for estimating the risk of frailty among elderly outpatients. Cross-sectional study at the Geriatrics Outpatient Clinic of a university hospital in Campinas. A non-probabilistic convenience sample of 150 elderly people of both sexes who were followed up as outpatients was assessed. Sociodemographic data (sex and age) and physical health data (frailty criteria and the five-times sit-to-stand test) were gathered. Descriptive, comparative and multivariate logistic regression analyses were performed. The majority of the elderly people (77.3%) were 70 years of age or over, with predominance of females (64.2%) and had a low score for the five-times sit-to-stand test (81.4% scored 0 or 1); 55.3% of the elderly people presented three or more frailty criteria. A significant association was found between lower-limb muscle strength and the variables of age and number of frailty criteria. Lower levels of lower-limb muscle strength were associated with advanced age and greater presence of signs of frailty. Moreover, lower-limb muscle strength was also associated with the criteria of reduced walking speed criteria and hand-grip strength
