Longitudinal patterns in physical activity and sedentary behaviour from mid-life to early old age: a substudy of the Whitehall II cohort.
BACKGROUND
There are few longitudinal data on physical activity patterns from mid-life into older age. The authors examined associations of self-reported physical activity, adiposity and socio-demographic factors in mid-life with objectively assessed measures of activity in older age.


METHODS
Participants were 394 healthy men and women drawn from the Whitehall II population-based cohort study. At the baseline assessment in 1997 (mean age 54 years), physical activity was assessed through self-report and quantified as metabolic equivalent of task hours/week. At the follow-up in 2010 (mean age 66 years), physical activity was objectively measured using accelerometers worn during waking hours for seven consecutive days (average daily wear time 891 ± 68 min/day).


RESULTS
Self-reported physical activity at baseline was associated with objectively assessed activity at follow-up in various activity categories, including light-, moderate- and vigorous-intensity activity (all ps<0.04). Participants in the highest compared with lowest quartile of self-reported activity level at baseline recorded on average 64.1 (95% CI 26.2 to 102.1) counts per minute more accelerometer-assessed activity at follow-up and 9.0 (2.0-16.0) min/day more moderate-to-vigorous daily activity, after adjusting for baseline covariates. Lower education, obesity and self-perceived health status were also related to physical activity at follow-up. Only age and education were associated with objectively measured sedentary time at follow-up.


CONCLUSIONS
Physical activity behaviour in middle age was associated with objectively measured physical activity in later life after 13 years of follow-up, suggesting that the habits in adulthood are partly tracked into older age.
Department of Epidemiology and Public Health, 1-19 Torrington Place, University College London, London WC1E 6BT, UK. m.hamer@ucl.ac.uk
Mark
M
Hamer
Mika
M
Kivimaki
Andrew
A
Steptoe
D061725:Accelerometry; D056044:Actigraphy; D050154:Adiposity; D000328:Adult; D000367:Age Factors; D000368:Aged; D000375:Aging; D015992:Body Mass Index; D005260:Female; D015438:Health Behavior; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D015999:Multivariate Analysis; D012307:Risk Factors; D057185:Sedentary Behavior; D057566:Self Report; D012959:Socioeconomic Factors