Exercise as it relates to Disease/Reducing the risk of CVD with daily physical activity in school children

The Paper analyzed was "Effects of a 2-year school-based daily physical activity intervention on cardiovascular disease risk factors: the Sogndal school-intervention study".

Analyzed by student u3119178

What is Cardiovascular Disease?
“Cardiovascular disease (CVD) is a collective term for diseases of the heart and blood vessels.”

The diseases classified under CVD include:
 * 1) 	Coronary heart disease
 * 2) 	Heart failure
 * 3) 	Cardiomyopathy
 * 4) 	Congenital heart disease
 * 5) 	Peripheral vascular disease
 * 6) 	Stroke

Why is it an issue?
CVD is a critical concern within the Australian health system. In 2012, 43,946 people died as a result of CVD, making it the leading cause of death within Australia. It also came out in front in regards to expenditure, an estimated $7,605 Million was spent on CVD in 08-09. This is a definite cause of concern, particularly when CVD is a highly preventable disease. CVD originates from risk factors, in which many can be controlled, modified, treated or prevented. Therefore making it an important issue to investigate.

Why School Children?
CVD mainly affects adults in their forties and onwards. However, research shows that atherosclerosis can begin during childhood. With CVD being a highly preventable disease it raises questions as to wether prevention strategies should begin earlier. The researchers of the current study aimed to determine wether an intervention within 9-year-old school children would help to reduce their CVD risk profile. Furthermore, developing healthy habits for them now is important, to help prevent later onset of CVD. School children were considered a good cohort for this study because of:

a)	Percentage of time spent within the school environment, allows for an aggressive intervention which can be conducted for long periods of time

b)	Large environment in means of accessing a large population from all backgrounds

c)	Clustering of risk factors in school children is seen to progress from childhood to adulthood

Where is the research from?
The research was collected from two different schools in two different cities approx. 100 km apart; Sogndal (intervention site) and Forde (control site) in rural Western Norway. Researchers in differing areas including: education and sport, sports science and clinical biomechanics, sports medicine and childhood health conducted the study. The paper was published in the Scandinavian Journal of Medicine and Science in Sports. Which is a peer reviewed academic journal.

What type of study was this?
This study was a controlled non-randomized design consisting of a physical activity intervention. “The aim of the study was to investigate the effect of a two-year school-based physical activity intervention in nine-year old school children on CVD risk factors”. Utilising a non randomized design, could be considered a limitation and bias, however other considerations were taken to minimise the effect of this.

What did the study involve?
This study had 174 fourth grade school children (born either 199 or 96) who successfully completed both the baseline and post intervention measurements for the two-year intervention. Measurements of CVD risk factors were taken both pre and post intervention. These measurements included: They were then split into two cohorts, 92 children were allocated to the intervention cohort (Sogndal school) and 82 to the control cohort (Forde school). The intervention group conducted 60 mins of physical activity lessons each school day. These lessons were planned and conducted by expert Physical Education (PE) teachers. They consisted of moderate to vigorous activity (approx. only 15 mins at a vigorous level), with time spent explaining activities and also conducting light intensity exercises for warm up and cool down. Lessons included a variety of activates to maintain interest and keep the lessons fun and enjoyable. The control group were allocated the prescribed amount of exercise stated within the curriculum; 2 x 45 min PE classes per week.
 * Body mass index (BMI)
 * Homeostasis model assessment
 * Waist circumference
 * Triglycerides
 * Systolic and diastolic blood pressure
 * Total cholesterol to high density lipoprotein ratio
 * Fitness (VO2peak)

Results
From the results table below there is a significant positive correlation between a physical activity intervention and 5 of the risk factors associated with CVD.

Conclusions
The study concluded that physical activity could be used as a tool to reduce CVD risk profiles in a children’s population. They stated however that the Physical activity would have to be of a substantial amount and should be implemented by expert PE teachers.

Practical advice
From the study it is evident that physical activity levels can be critical to preventing CVD and its associated risk factors. Although it is also clear that it would be quite difficult to implement an extra 60min class into the school curriculum. In addition to this however, school is an environment in which children and adolescents spend majority of their time, from ages 6–16. Therefore a practical suggestion would be to add pre and post school care, similar to after care, in which exercise programs could be run. It would also be suggested that an overall standardized curriculum be written which is easily reproducible.

Overall
To conclude this study shows that physical activity could be an effective positive intervention for children to reduce their CVD risk profile but to also build healthy habits for their future. Thus helping to prevent and minimise incidence of CVD in a future setting. Overall the researchers have provided a strong study that has presented useful results and information surrounding physical activity and cardiovascular disease risk factors in children.