Associations between objectively measured physical activity, sedentary behaviour and time in bed among 75+ community-dwelling Danish older adults.

ABSTRACT:

Background

Older adults are recommended to sleep 7-8?h/day. Time in bed (TIB) differs from sleep duration and includes also the time of lying in bed without sleeping. Long TIB (?9?h) are associated with self-reported sedentary behavior, but the association between objectively measured physical activity, sedentary behavior and TIB is unknown.

Methods

This study was based on cross-sectional analysis of the Healthy Ageing Network of Competence (HANC Study). Physical activity and sedentary behaviour were measured by a tri-axial accelerometer (ActiGraph) placed on the dominant wrist for 7?days. Sedentary behavior was classified as ResultsThree hundred and fourty-one older adults (median age 81 (IQR 5), 62% women) were included with median TIB of 8?h 21?min (1?h 10?min)/day, physical activity level of 2054 (864) CPM with 64 (15) % of waking hours in sedentary behavior. Those with average CPM within the highest tertile had a lower RRR (0.33 (0.15-0.71), p?=?0.005) for being RTIB compared to those within the lowest tertile of average CPM. Accumulating physical activity in intensities 2303-4999 and???5000?cpm/day did not affect the RRR of being RTIB. RRR of being RTIB among highly sedentary participants (?10?h/day of sedentary behavior) more than tripled compared to those who were less sedentary (3.21 (1.50-6.88), p?=?0.003).

Conclusions

For older adults, being physically active and less sedentary was associated with being in bed for 7-9?h/night for most nights (?80%). Future longitudinal studies are warranted to explore the causal relationship sbetween physical activity and sleep duration.

SUBMITTER: Tsai LT 

PROVIDER: S-EPMC7807682 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature