title: Daily activity patterns of 2316 men and women from five countries differing in socioeconomic development.
abstract: Daily rhythmicity in the locomotor activity of laboratory animals has been studied in great detail for many decades, but the daily pattern of locomotor activity has not received as much attention in humans. We collected waist-worn accelerometer data from more than 2000 individuals from five countries differing in socioeconomic development and conducted a detailed analysis of human locomotor activity. Body mass index (BMI) was computed from height and weight. Individual activity records lasting 7 days were subjected to cosinor analysis to determine the parameters of the daily activity rhythm: mesor (mean level), amplitude (half the range of excursion), acrophase (time of the peak) and robustness (rhythm strength). The activity records of all individual participants exhibited statistically significant 24-h rhythmicity, with activity increasing noticeably a few hours after sunrise and dropping off around the time of sunset, with a peak at 1:42 pm on average. The acrophase of the daily rhythm was comparable in men and women in each country but varied by as much as 3 h from country to country. Quantification of the socioeconomic stages of the five countries yielded suggestive evidence that more developed countries have more obese residents, who are less active, and who are active later in the day than residents from less developed countries. These results provide a detailed characterization of the daily activity pattern of individual human beings and reveal similarities and differences among people from five countries differing in socioeconomic development.
authors.affiliation: Circadian Rhythm Laboratory, Department of Psychology, Boise State University , Boise, ID , USA .
authors.forename: Mamane
authors.initials: M
authors.lastname: Sani
authors.forename: Roberto
authors.initials: R
authors.lastname: Refinetti
authors.forename: Girardin
authors.initials: G
authors.lastname: Jean-Louis
authors.forename: S R
authors.initials: SR
authors.lastname: Pandi-Perumal
authors.forename: Ramon A
authors.initials: RA
authors.lastname: Durazo-Arvizu
authors.forename: Lara R
authors.initials: LR
authors.lastname: Dugas
authors.forename: Ruth
authors.initials: R
authors.lastname: Kafensztok
authors.forename: Pascal
authors.initials: P
authors.lastname: Bovet
authors.forename: Terrence E
authors.initials: TE
authors.lastname: Forrester
authors.forename: Estelle V
authors.initials: EV
authors.lastname: Lambert
authors.forename: Jacob
authors.initials: J
authors.lastname: Plange-Rhule
authors.forename: Amy
authors.initials: A
authors.lastname: Luke
mesh_terms: D056044:Actigraphy / Q000379:methods; D000203:Activities of Daily Living; D000328:Adult; D001519:Behavior / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D012959:Socioeconomic Factors
keywords: Actigraphy; behavior; circadian rhythms; cross-national comparison; human mobility