A Real-Time Web-Based Intervention with a Multicomponent Group-Based Program for Older Adults: Single-Arm Feasibility Study.

Frailty is a growing public health challenge in Japan's rapidly aging population, where 28.8% are aged ≥ 65. While multicomponent interventions have shown potential in preventing frailty, traditional face-to-face programs face accessibility challenges. This study evaluated the feasibility and short-term changes of an online multicomponent intervention on frailty-related factors among community-dwelling older adults. In this single-arm feasibility study, 132 participants (mean age 75.7; standard deviation 4.8 years, 65.2% women) completed a six-week online intervention combining exercise, nutrition education, cognitive activities, and the Coimagination Method to foster social connections, meeting weekly for 75 min sessions in groups of up to 10 participants. The intervention demonstrated feasibility with a 96.4% retention rate and a 94.0% average participation rate. While no significant changes were observed in physical activity levels, autonomic nervous system indicators, or cognitive function, carotenoid scores and hemoglobin concentration improved significantly, with more pronounced improvements among women than men. This study demonstrates the high feasibility of online multicomponent interventions for older adults and suggests potential benefits for nutritional status markers, particularly among women. These findings indicate a promising and accessible approach to frailty prevention, though randomized controlled trials with longer intervention periods and direct frailty assessments are required to establish effectiveness conclusively. Study Trial registration: UMIN Clinical Trials Registry (UMIN000053089).