Intervention for Social Frailty Focusing on Physical Activity and Reducing Loneliness: A Randomized Controlled Trial

During the COVID-19 pandemic, older adults living in the community experienced reduced physical activity (PA) and heightened loneliness, particularly those with less frequent outings-a key factor of social frailty. Promoting PA may foster social participation, increase outings, and reduce loneliness. This study investigates the effects of a multi-component intervention on PA and loneliness in socially frail older adults. This single-blind, randomized controlled trial included 64 participants aged ≥ 60 years with social frailty and pre-frailty defined according to Makizako's Social Frailty Index. Participants were randomly assigned to either the intervention (n = 34) or the control (n = 30) group. Over eight weeks, the intervention group attended a weekly 60-min multi-component program that included health education, exercise, and self-monitoring. A simple exercise booklet was distributed to the control group at baseline. For both groups, outcome measures were assessed at baseline and after eight weeks. PA was assessed using a triaxial accelerometer. Loneliness was measured using the three-item version of the UCLA Loneliness Scale. We used repeated-measures analysis of variance with group-by-time interactions to estimate the intervention effects following the intention-to-treat approach. PA was not affected by the intervention. A significant group-by-time interaction was observed for loneliness, with a medium effect size (p < 0.05), indicating that loneliness was significantly reduced in the intervention group compared to the control group. The multi-component program aimed at promoting PA may contribute to the building of social relationships and reducing loneliness in older adults with social frailty and pre-frailty.