Culturally adapted wearable mobile health intervention for physical activity and cognitive function in middle-aged Koreans: a pilot feasibility study

BACKGROUND: Middle adulthood (45-64 years) represents a critical window for the primary prevention of cognitive decline and chronic diseases, with physical activity capable of reducing later cognitive decline by 20% to 35%. However, most evidence on mobile health (mHealth) interventions for physical activity originates from Western populations, with limited evaluations of culturally adapted approaches for Asian middle-aged adults, particularly in rapidly aging societies such as South Korea. METHODS: This 12-week, single-arm, pre-post pilot feasibility study enrolled 304 community-dwelling adults aged 45 to 64 years from Dobong-gu, Seoul, South Korea. The intervention combined a Samsung Galaxy Watch 6 with a custom mobile application incorporating culturally adapted features (mountain-climbing gamification based on famous Korean peaks, adaptive goal setting, and context-aware notifications) developed through systematic focus groups. The primary outcomes were weekly step count and moderate-to-vigorous physical activity (MVPA), while the secondary outcomes included subjective cognitive function assessed using a validated self-report scale, exercise behavior stages, depressive symptoms, and app usability. RESULTS: Of the 304 participants, 302 (99.3%) completed the intervention. Weekly step count increased by 16.9% from 78,334 to 91,531 (p<0.001) and weekly MVPA increased by 83.3% from 56.0 to 102.6 minutes (p<0.001). The proportion of participants meeting the World Health Organization physical activity guidelines increased from 23.2% to 42.1% (p<0.001). Selective improvements were observed in executive function-related cognitive domains and depressive symptoms, and a dose-response relationship emerged between app engagement and step count gains. CONCLUSION: This culturally adapted wearable mHealth intervention demonstrated high feasibility and acceptability for promoting physical activity in Korean middle-aged adults, supporting its further evaluation as a scalable strategy for the primary prevention of cognitive decline and chronic diseases.