Swedes are less active than we think we are
[NEWS 20 April 2010] Swedish younger males are less active than US younger males. Swedish females have higher physical activity than US females, across all age groups. This is shown in a first time ever comparison of physical activity between two countries population. The results was newly published by researchers from Karolinska Institutet in the scientific journal "American Journal of Epidemiology"
To date, international comparisons of physical activity levels in adults have been based on self-report. Social desirability bias and the cognitive challenge of recalling behaviour from the past are some of the limitations of self-report. Therefore, the interest in objective physical activity monitoring has increased. The accelerometer is a monitor providing minute-by-minute registration of diverse activities which has now been used by researchers in Sweden and the United States to objectively assess national physical activity. The technique has been developed and refined by Sjöström and colleagues at Karolinska Institutet.
The researchers followed 1172 Swedish participants and 2925 US participants during one week. Their level and pattern of physical activity was then analysed with regard on differences on their age, sex, height, weight and educational attainment.
Contrary to expectations based on past studies with self reported physical activity, levels of physical activity were not uniformly higher in Sweden. Older Swedes were more active than older US respondents, but in the lowest education group, the US males had significantly higher counts per minute compared with the lowest education group in Sweden. However, mean counts per minutes were 5 % - 25 % higher for Swedish females than for US females across age, body mass index and education groups.
The results provide a framework for international comparison of physical activity levels and pattern and they represent a strong evidence for the importance of investment in objective measurement of physical activity.
Levels and Patterns of Objectively assessed Physical Activity - a Comparison between Sweden and the United States
American Journal of Epidemiology, Epub ahead of print, 20 April 2010, DOI: 10.1093/aje/kwq069.