Hospital inpatient care is a significant source of expense for the healthcare system. In this study the objectivewas to verify the existence of an association between physical inactivity during free time (IFTL) and IHTC (hospital admissions for whatever cause), due to cardiac problems (IHPC) and diabetes (IHD) in adults in the city of Salvador in Brazil. This was a cross-sectional study of a sample of 2290 adults ≥ 20 years of age, 1021 (44.6%) being men. Subjects were defined as IFTL if they stated that they did not take part in physical activity during leisure time, while hospital admissions were self-reported. Logistic regression analysis was used to estimate the odds ratio (OR) between IFTL, IHTC, IHPC and IHD to a confidence interval of 95%. Multivariate analysis was then applied and detected an association between IFTL, IHTC, IHPC and IHD in men, while among the women there was only an association between IFTL and IHD. The results of this study are of importance for public health, to the extent that they could be used to facilitate the management of programs to encourage participation in physical activities with a view to preventing hospital admissions and consequently to reducing the costs to the health system.