Objectively measured physical activity and sedentary time in youth: the International children's accelerometry database (ICAD)
journal contributionposted on 27.11.2015, 13:43 by Ashley R. Cooper, Anna Goodman, Angie S. Page, Lauren SherarLauren Sherar, Dale EsligerDale Esliger, Esther M.F. van Sluijs, Lars Bo Andersen, Sigmund Anderssen, Greet Cardon, Rachel Davey, Karsten Froberg, Pedro Hallal, Kathleen F. Janz, Katarzyna Kordas, Susi Kreimler, Russ R. Pate, Jardena J. Puder, John J. Reilly, Jo Salmon, Luis B. Sardinha, Anna Timperio, Ulf Ekelund
Background Physical activity and sedentary behaviour in youth have been reported to vary by sex, age, weight status and country. However, supporting data are often self-reported and/or do not encompass a wide range of ages or geographical locations. This study aimed to describe objectively-measured physical activity and sedentary time patterns in youth. Methods The International Children’s Accelerometry Database (ICAD) consists of ActiGraph accelerometer data from 20 studies in ten countries, processed using common data reduction procedures. Analyses were conducted on 27,637 participants (2.8–18.4 years) who provided at least three days of valid accelerometer data. Linear regression was used to examine associations between age, sex, weight status, country and physical activity outcomes. Results Boys were less sedentary and more active than girls at all ages. After 5 years of age there was an average cross-sectional decrease of 4.2 % in total physical activity with each additional year of age, due mainly to lower levels of light-intensity physical activity and greater time spent sedentary. Physical activity did not differ by weight status in the youngest children, but from age seven onwards, overweight/obese participants were less active than their normal weight counterparts. Physical activity varied between samples from different countries, with a 15–20 % difference between the highest and lowest countries at age 9–10 and a 26–28 % difference at age 12–13. Conclusions Physical activity differed between samples from different countries, but the associations between demographic characteristics and physical activity were consistently observed. Further research is needed to explore environmental and sociocultural explanations for these differences.
This work was supported by the UK Medical Research Council National Prevention Research Initiative (NPRI) [grant number G0701877]. Funding partners are: British Heart Foundation; Cancer Research UK; Department of Health; Diabetes UK; Economic and Social Research Council; Medical Research Council; Research and Development Office for the Northern Ireland Health and Social Services; Chief Scientist Office, Scottish Executive Health Department; The Stroke Association; Welsh Assembly Government and World Cancer Research Fund. AC is supported by the National Institute for Health Research Bristol Nutrition Biomedical Research Unit based at University Hospitals Bristol NHS Foundation Trust and the University of Bristol. AG is funded by a post-doctoral fellowship from the National Institute of Health Research (NIHR). The views expressed in this paper are those of the author(s) and not necessarily those of the study funders, NHS, the NIHR or the Department of Health. JS is supported by a Principal Research Fellowship from the National Health & Medical Research Council of Australia (APP1026216). AT is supported by a Future Leader Fellowship from the National Heart Foundation of Australia (Award ID 100046).
- Sport, Exercise and Health Sciences