Exercise and success in school

If you’ve read any of my previous posts, you might have noticed I mainly focus on factors that are proposed as helpful or harmful to the ageing brain (recent posts have considered research examining how cocoa or cleanliness might be associated with cognitive changes in old age, for example). However, our cognitive performance in later life is strongly determined by our cognitive development across the lifecourse. A critical question is therefore: “what factors might promote the development of our mental skills throughout childhood and adolescence?” A recent study which was widely reported in the media (the Scotsman and Express, for example) addressed this by examining how physical activity was associated with academic attainment in children of secondary school age.

What did the research say?

The study was led by Dr Josie Booth from the School of Psychology at the University of Dundee, in collaboration with colleagues from across the UK and USA. They used data from a large, ongoing study known as the Avon Longitudinal Study of Parents and Children (ALSPAC), coordinated from the University of Bristol. For their analysis, the researchers used data from 4755 children who had their physical activity assessed at age 11, and then examined how this was associated with their academic attainment at ages 11, 13 and 16. Physical activity was measured using a device called an accelerometer, a simple instrument that measures movement, and children wore this for up to 7 days in total (though the researchers were able to include the children if they had data recorded over at least 3 days, and at least 10 hours of information on each of those days). The output from the accelerometer was in counts per minute, and from their previous work, the researchers had calculated that 3600 counts per minute was equivalent to moderate-vigorous physical activity. The accelerometer data was therefore used to define how much physical activity the children took overall, and also the percentage of this which would be considered as moderate-vigorous intensity physical activity.

As the study reported attainment in three different subjects (English, Maths and Science), at three ages (11, 13 and 16 years old) in both boys and girls, the detailed results can’t be easily summarised here. In general, however, children doing more moderate-physical activity had higher attainment across all subjects, and this was true for both boys and girls. When a number of possible confounding factors were included, such as mother’s age and smoking status, her educational attainment and social class, etc., some of the associations held and other didn’t. For example, in the analysis included these potential confounders, the most consistent results appeared to be with English attainment; for both boys and girls and across all three ages, more moderate-vigorous physical activity at age 11 was associated with better performance. For boys, the inclusion of these confounders made the results less clear for Maths, and Science attainment no longer appeared to show a benefit. For girls, both Maths and Science attainment at age 16 remained associated with moderate-vigorous physical activity (although the results with Maths would be considered on the borderline of statistical significance).

With studies in humans, we’re often interested in how one factor might predict another (like in this example, how might the level of physical activity predict academic success?). Studies might measure both these things simultaneously. In that sort of design, we might see that the two factors are associated, but we can’t make strong claims about which one precedes or predicts the other. One of the strengths of this study is that it has a longitudinal element, that is, it follows the same individuals over time. This is particularly important when the outcome we’re interested in is something that can develop or change. Other strengths to the current study were the large sample size, allowing boys and girls to be analysed separately, the fact that physical activity was measured objectively not just from self-report questionnaires, and that attainment in a range of subjects was considered.

What did the media say?

As noted above, both the Express and Scotsman (among other media outlets) reported the findings of this study. Both gave a balanced reporting of the main findings (the overall benefit of moderate-vigorous physical activity), while the nuances of the main results could only be covered briefly. The Scotsman‘s coverage was particularly good, however, in citing the scientific journal the original study was published in, and quoting from two of the study authors.

The bottom line?

Ensuring that children develop their full potential is important not just for the individuals themselves in terms of current and future academic or occupational attainment, but also because development in early childhood and adulthood casts a long shadow over future health and wellbeing. The current study highlights how few children attain the recommended level of physical activity (about 60 minutes per day), but suggests that the impact of increasing this might be measurable in terms of academic success.

Booth, J. N., Leary, S. D., Joinson, C., Ness, A. R., Tomporowski, P. D., Boyle, J. M., & Reilly, J. J. (2013). Associations between objectively measured physical activity and academic attainment in adolescents from a UK cohort. British Journal of Sports Medicine. doi:10.1136/bjsports-2013-092334