This article presents a dataset of body composition, strength and performance measurements in older adults; the data were collected as part of Rancho Bernardo Study (RBS), a longitudinal observational cohort study. All community dwelling adults in Rancho Bernardo, California between 1972 and 1974 were eligible for participation in the study. A subset of the participants returned every four years for subsequent visits. The dataset in this publication consists of some of the measures taken in Visits 7-10, for 1466 subjects who had at least one of these measures taken. We analysed the data with a feed-forward loop model fitted by structural equation modelling. The data can be valuable for modelling and extracting further information on how body composition, strength and performance affect each other over a long period of time. The data are analysed and interpreted in the research article RoyChoudhury et al., 2019.