Daily sedentary time and physical activity as assessed by accelerometry and their correlates in older adults.

Background: Higher physical activity is associated with lower chronic disease risk among older adults. However, less is known about the optimal balance between daily physical activity and sedentary time and their correlates among older adults. We described objectively measured physical activity patterns using 7 day hip-accelerometry and assessed its correlates in a large cross-sectional sample of the Longitudinal Aging Study Amsterdam, a population-based cohort of older Dutch adults. In addition, we examined different combined profiles of sedentary time and physical activity across strata of sex, age, education and BMI groups.

Results: Mean age was 71 (SD 8) years and 51% ( = 615) were women. The majority of wear time was spent sedentary (65%) followed by light (33%), and MVPA (2%). Higher age and higher BMI were related to more time spent sedentary, while female sex and lower education were related lower sedentary time. The combination of high sedentary time (≥65.4% of waking time) and low physical activity (< 9.1% of waking time) was significantly associated with higher age, higher BMI, and slower walking speed compared to the combination of low sedentary time and high physical activity  < 0.001.

Conclusions: Dutch older adults spend on average 65% of their waking time sedentary. Older adults' sedentary time differs by age, sex, education and BMI groups. The combination of high sedentary time and low physical was associated with higher age, higher BMI, and slower walking speed compared to the combination of low sedentary time and high MVPA. This suggests that increasing light activity might be an effective and feasible strategy in older persons to reduce sedentary time. Future studies should assess whether low- sedentary and high-light physical activity are associated with improved long-term health outcomes (also independent of MVPA).