Internet use and physical activity among family caregivers of older adults: Evidence from the China Health and Retirement Longitudinal Study

•This study analyzes the relationship between Internet use and physical activity for family caregivers of older adults.•Internet use was negatively associated with MVPA while had no correlation with LPA.•The relationship between Internet use and MVPA was mediated by participation in economic activities, while participation in social activities acted as a suppressor.•The association between Internet use and MVPA was only reported in rural family caregivers. This study examined the influence of Internet use on light-intensity physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) among family caregivers of older adults, utilizing data from the 2018 China Health and Retirement Longitudinal Study (N = 3,194). The Tobit model and Propensity Score Matching were first used to test the focal associations. Subsequently, mediation analyses and heterogeneity analysis were conducted to explore the pathways and urban-rural disparities. The results indicated that Internet use was negatively associated with MVPA and was not correlated with LPA. The Internet use – MVPA relationship was mediated by participation in economic activities, while participation in social activities acted as a suppressor. Further, the focal association was only found in rural family caregivers. The findings suggest that effective health promotion interventions are needed to mitigate the negative influence of Internet use on the MVPA of family caregivers of older adults, especially for those in the rural.