Measuring physical activity in preschool children

A technical challenge

The UK Physical Activity Guidelines recommend that preschool children (under fives) should be physically active for at least 180 minutes per day. This is important for a child’s development, for reducing the risk of childhood obesity and for establishing healthy habits that continue across the lifespan.

However, accurately measuring physical activity in children is very challenging because their play is often unpredictable and intermittent. Nevertheless, Dr Roscoe, Senior Lecturer in Physical Activity and Health in our College of Science and Engineering, was undaunted.

Through research that began as her PhD, Dr Roscoe and colleagues became the first people to determine suitable ‘cut-points’ (points of separation in the data) for preschool children wearing GENEActiv accelerometers. The children wear these on their wrist like a watch.

Dr Roscoe explains: “An accelerometer is an electromechanical device used to measure acceleration forces. Age-appropriate cut-points need to be determined so that it’s possible to classify the readings from the device into meaningful categories, such as ‘sedentary behaviour’, ‘light’, ‘moderate’ and ‘vigorous’ physical activity.

“Using this quantitative data as well as qualitative data from focus groups performed with parents and preschool staff, I was able to measure the children’s activity during the week and at the weekend.”

Worrying findings

Dr Roscoe found that the preschool children did not participate in the recommended 180 minutes of physical activity every day. She also found that they were significantly more sedentary on weekend days (96.9%) compared with weekdays (91.9%). They only participated in 6.3% of moderate to vigorous physical activity in the weekdays and 2.0% during the weekend days.

These figures are alarming and should be used to promote future interventions to enhance physical activity and encourage the preschool children to participate in more light and ideally moderate-to-vigorous physical activity during both the week and weekend days.

“One recommendation from the research”, says Dr Roscoe, “is that training in physical activity and fundamental movement skills is made mandatory for all staff working with preschool children.

"But, clearly, the home environment is important too if we are going to decrease sedentary behaviour during weekends. Parents need to be more supportive in promoting physical activity so children have the chance to grow to be healthy adults.”