Same old, same old: Daily sequence and well-being in later life using ecological momentary data.

OBJECTIVES: Understanding whether daily routine reflects adaptive stability or constrained opportunities for enrichment remains an open question in aging research. METHODS: This study develops a Weekly Routine Index (WRI) using Ecological Momentary Assessment (EMA) data from 253 older adults in the Social Environment and Cognitive Health in Urban and Rural Areas (SECHURA) to quantify within-person similarity in daily activities and co-presence with social partners (4,025 total EMAs). We computed pairwise similarities between each respondent's daily sequences to generate activity- and co-presence-based routine similarity measures. RESULTS: Regression and correlational analyses show that both routine similarities increase modestly with age and are higher among men and unmarried individuals. Importantly, stability in both activity and co-presence sequences is associated with lower cognitive functioning, more functional limitations, higher loneliness, and smaller, less diverse social networks. DISCUSSION: These findings suggest that stability in later life may not be uniformly beneficial; rather, highly routinized daily schedules may co-occur with limited exposure to socially and cognitively enriching experiences linked to healthy aging. This study also demonstrates the value of applying sequence analysis to EMA data to capture the temporal structure of later life.