The question:

How active are the primary school children in our study?

This question will relate to all other areas in one way or another and fundamental to all research areas.

Accurately measuring physical activity (PA) is a challenging task largely due to the variation in leisure time and work activities humans can perform. The variables used to describe PA; intensity, duration, type and frequency are prone to measurement error, and are often context specific.

Measuring physical activity in children is more challenging than in any other population. This is largely due to children's lesser ability to use self report techniques due to their cognitive development. The very nature of children's activity which is largely unstructured and sporadic and usually at lower intensities further complicates the measurement procedure as does the nature of children themselves.

We have decided to use pedometers together with reports from the parents and children to estimate the physical activity levels and patterns of the children. Pedometers are battery powered step counters that are designed to measure steps taken and distance over a period of time. Pedometers are low in cost and easy to use but are limited by their inability to provide detail on frequency or intensity of activity.