Accelerometer assessment of physical activity and its association with physical function in older adults residing at assisted care facilities

Objectives To describe levels of physical activity among older adults residing at assisted care facilities and their association with physical function. Design Cross-sectional analysis. Setting Assisted care facilities within the greater Boston, MA area. Participants Older adults aged 65 years and older (N = 65). Measurements Physical Activity Level (PAL) as defined by quartiles from accelerometry (counts and steps), Short Physical Performance Battery (SPPB) Score, gait speed, and handgrip strength. Results Participants in the most active accelerometry quartile engaged in 25 minutes/week of moderate to vigorous physical activity (MVPA) and walked 2,150 steps/day. These individuals had an SPPB score, 400 meter walk speed, and handgrip strength that was 3.7–3.9 points, 0.3–0.4 meters/second, and 4.5–5.1 kg greater respectively, than individuals in the lowest activity quartile, who engaged in less than 5 min/wk of MVPA or took fewer than 460 steps/day. Conclusion Despite engaging in physical activity levels far below current recommendations (150 min/week of MVPA or > 7000 steps/day), the most active older adults in this study exhibited clinically significant differences in physical function relative to their less active peers. While the direction of causality cannot be determined from this cross-sectional study, these findings suggest a strong association between PAL and physical function among older adults residing in an assisted care facility.