Steadily declining physical activity, especially among children, and the possible adverse health outcomes such behavior could precede, is a general concern. We evaluated whether a presumed decrease in physical activity has been accompanied with a decrease in aerobic fitness of Swedish children.
A maximum cycle ergometer test was performed in 935 children age 9 and 15 y, and the results were compared with previously reported data.
Estimated peak oxygen uptake (mL × min-1 × kg-1) in 9-y-old subjects was 37.3 in girls and 42.8 in boys; and in 15-y-olds, 40.4 in girls and 51.5 in boys. In the 9-y-olds, aerobic fitness remained lower in the current study compared to earlier data, but in the 15-y-olds the result did not differ from the 1952 data after adjustment for methodological differences.
Our results suggest a change towards decreased aerobic fitness in 9-y-old, but not in 15-y-old, Swedish children during a 50-y time span.