Exercise as it relates to Disease/Does the structure of the school day impact children's levels of physical activity outside of school?
What is the background to this research?
This research paper seeks to identify whether there is a relationship between the level of physical activity undertaken by children while at school, and whether this impacts their PA levels outside of school hours. This is a gap commonly found in literature as most studies revolve around influencing factors such as the physical environment or parenting factors 
In 2016, the World Health Organisation stated that 41 million children under the age of 5 were overweight or obese, while 340 million children and adolescents were overweight or obese . With research proving that in conjunction with healthy eating, physical activity is a critical factor in both maintaining health and losing weight , it becomes clear as to why studies such as this are important for helping to combat childhood obesity.
Where is the research from?
Darren Dale worked in the Department of Health, Kinesiology and Leisure Studies at Purdue University, while Charles B. Corbin worked with the Department of Exercise Science and Physical Education at Arizona State University. Both of these men were highly regarded for their studies in the children and adolescents health and physical education field, and have produced many high quality papers throughout their years in the field. Kathleen S. Dale also provided valuable contribution to the study through her role at Mt. Carmel Elementary School in Tempe, Arizona.
Throughout the study it does not appear as though there is any sort of bias which may be created by either organisational or sponsorship links that could generate a conflict of interest. The only significant mention of another party which may have created a conflict in interest is the use of the specific 'Computer Science and Applications Accelerometer (CSA)', but this is merely to provide detail about the devices that were used.
What kind of research was this?
This research paper utilises a quasi-experimental research design to help reach its desired outcomes. A quasi-experimental design functions by manipulating an independent variable in the attempt to then record changes in another set of variables .
In the instance of this research, the independent variable which is being altered is the structure of the schooling day surrounding whether or not there is physical activity being scheduled. This is then intended to impact the dependent variable of whether there is an increase or decrease in the amount of physical activity which is completed outside of school hours.
In regards to the validity of the quasi-experimental design, there are four key points surrounding the model;
- Can only test casual hypothesis
- Lacks random assignment to test groups
- Identify a comparison group as similar as possible to treatment group
- Different techniques for creating a valid comparison group 
This provides both positive and negative factors, as with most research methods, but succeeds in reaching the intended set of results in identifying a trend in physical activity outside of school hours.
What did the research involve?
This research sought to determine whether the structuring of the school day had an impact on the level of physical activity that children complete outside of school hours. The study observed 76 children from both third and fourth grade using a CSA accelerometer to track activity throughout the day. Children were tracked for a total of four days throughout a 14-week period, two of these days being 'active' and two being 'restricted'. An active day was defined as a school day where children participated in physical education classes and outdoor recess play, while restricted days involved children staying inside during recess and not having scheduled physical education class . The recorded time frames of activity were 9am-3pm (during school) and 3pm-7:30pm (after school).
The study utilised the approach of qualitative research in conjunction with having a set of variables to determine results of the study. The three variables of the study were Independent (School day structure), Dependent (Student activity level) and Constant (CSA Accelerometer). Identifying these three variables is a crucial step, as it is highly important to know which variable can be changed to assist in finding the correct information . In relation to the objectives of this study, a method such as this is the most effective way of conducting the research due to its ability to account for numerous aspects which are all seeing changes occur.
What were the basic results?
The study found that there was a direct link between the structuring of the school day and the amount of physical activity which was conducted outside of school hours. On days where children participated in a scheduled physical education class and were able to play outside during recess , it was shown that there was almost 3 times as much physical activity completed outside of school hours (3pm-7:30pm) when compared to school days with no scheduled activity and restriction to being inside during recess .
Upon the conclusion of this report, the major hypothesis was made surrounding the importance of having central nervous system (CNS) arousal in children and the impact of lowering their energy expenditure. It was initially argued that limiting children's amount of physical activity during the school day would then lead to them compensating for this through an increase of activity after the school day. The findings of this research found this to be incorrect, as children's amount of physical activity was lower on the days where their activity was limited throughout the school day.
What conclusions can we take from this research?
From the findings of this research we can begin to draw the conclusions that the structuring of the school day does have a direct impact on the amount of physical activity which children complete outside of school hours. There was a strong link established between children participating in scheduled physical activity classes and increased physical activity levels. It was hypothesised that the lack of stimulation of the CNS from a sedentary school day would lead to increases in activity outside of school as compensation, although this was not the case. This is likely because the limited stimulation of the CNS contributes to a fatiguing of the system, therefore leading to lower energy levels in the system .
It is agreeable that this hypothesis is highly likely as being the key contributing factor to this scenario, and difficult to be argued due to the lack of other literature addressing this topic.
Although there are strong hypothesis made about reasons why physical activity is not made up for outside of school hours, there are still numerous areas which may provide implications to the results. Some factors which may have impacted the accuracy of results are;
- The family commitments of children outside of school hours on active/non-active days
- Scheduled sports training after school hours
- The children's dietary intake on a particular day (low energy or high energy intakes)
- Amount/urgency of homework having to be completed outside of school
A study like this would greatly benefit from having a method of follow on approach regarding how children can fit physical activity into their day. This could be through the implementation of a physical activity education program, where children are better informed about the importance of incorporating enough activity into their day, and examples of how they can account for this.
Further information for this specific topic is difficult to find as there is not research done specifically in this area. Content surrounding children's health can be found at the following sites;
- Child activity guidelines - World Health Organisation
- Children 5-12 years - Australian Activity Guidelines
- Motivating Kids to Be Active
- Heart Foundation - Get Active
- Australian Medical Association
- Brustard, R.J. et al. (1993) 'Who Will Go Out and Play? Parental and Psychological Influences on Children's Attraction to Physical Activity'. Pediatric Exercise Science vol. 5 pp 210-223
- World Health Organisation (2018). "Obesity and Overweight." from https://www.who.int/news-room/fact-sheets/detail/obesity-and-overweight.
- Serdula M.K et al. (1999) 'Prevalence of Attempting Weight Loss and Strategies for Controlling Weight'. American Medical Association vol. 282(14) pp1353-1358
- Research Gate (2019) "Charles B Corbin's research while affiliated with Arizona State University and other places." from https://www.researchgate.net/scientific-contributions/11003203_Charles_B_Corbin
- Dale, D et al. (2000) ‘Restricting opportunities to be active during school time: Do children compensate by increasing physical activity levels after school?. Research Quarterly for Exercise and Sport vol. 71(3) pp240-248
- Campbell, D and Stanley, J. (1963) ‘experimental and quasi-experimental designs for research’. Handbook of research on teaching
- White, H and Sabarwal, S. (2014) ‘Quasi-experimental design and methods’. UNICEF – Methodological Briefs, Impact Evaluation vol. 8 pp 1-12
- Duggan, S et al. (1996) ‘A critical point in investigative work: defining variables. Journal of Research in Science Teaching vol. 33(5) pp461-474
- Beardsley, C (2019). ‘Why does central nervous system (CNS) fatigue happen during strength training?’. A Medium Corporation. Available at; https://medium.com/@SandCResearch/why-does-central-nervous-system-cns-fatigue-happen-during-strength-training-e0af3f5e4989