Trends in physical activity and participation in sports clubs among Icelandic adolescents.

BACKGROUND: Physical activity among adolescents and its implications for health status is of increasing concern. We examined trends in physical activity and participation in sports clubs among Icelandic adolescents.
METHODS: Cross-sectional survey data were used to determine levels of vigorous physical activity and participation in sports clubs (defined as engaging in moderately intensive activity four times or more a week) for cohorts of Icelandic adolescents in 1992, 1997, 2000 and 2006.
RESULTS: There was a 6% increase in the rate of vigorous physical activity and a 15% increase in active sports club participation among 14- and 15-year old Icelandic adolescents from 1992 to 2006. The trends were consistent across genders; however, only 53% of boys actually achieved the recommended criterion for vigorous physical activity, with the percentage of girls averaging 16% lower than that for boys. Additionally, there was an overall increase in the proportion of inactive adolescents, with girls consistently reporting higher levels of inactivity than boys even though the net increase in inactivity was higher for boys.
CONCLUSION: Although our results show an overall increase in vigorous physical activity and participation in sports clubs over the past decade among both genders, our data also indicate that over half of all Icelandic adolescents are not achieving the recommended level of participation in physical activity. Furthermore, less than one third of the population studied is achieving the recommended level of activity through organized clubs. Initiatives to increase physical activity among the least active of adolescents should receive high priority in public health.