Exercise as it relates to Disease/Physical activity in urban school-aged children with asthma

This is a critique of the original research article “Physical Activity in Urban School-Aged Children with Asthma” by D.M Lang et al. (2004)

What is the background to this research?
Asthma is a common chronic lung disease that affects an individual’s ability to breathe with ease. According to the National Asthma Council of Australia, asthma was responsible for the deaths of 455 Australians in 2016.

Asthma is characterized by airflow obstruction which is caused by inflammation of the airways. Individuals with asthma are known to have highly sensitive airways, which causes the immune system to react to environmental triggers. When inflamed the airways become temporarily narrow and thick with mucous, restricting airflow in and out of the lungs.

Exercise Induced Asthma (EIA) is a temporary narrowing of the airways which is instigated by vigorous exercise or cold air exposure. Typically, it is believed that asthma sufferers should avoid exercise as a method for reducing the occurrence of an attack. However, physical activity is important in the management of asthma as increased fitness is linked to decreased severity of asthma symptoms.

In addition to the asthma related benefits, physical activity reduces the prevalence of poor health and chronic diseases, and is an important part in the development of healthy habits in children. This is especially important as older adults with asthma are found to be twice as likely to suffer from other chronic diseases such as diabetes, arthritis, heart disease and cancer.

The study conducted by Lang et al, observed whether diagnosis of asthma impacted the child’s level of physical activity in comparison to their counterparts.

Where is the research from?
The research undertaken for this study was conducted in the Harriet Lane Pediatric Clinic, in Baltimore, Maryland. The research was supported by a grant from the Thomas Wilson Foundation, an organisation dedicated to improving the health of Children in Baltimore.

Dr Lang has been well recognised for his achievements in medicine, and has been certified by the American Board of Internal Medicine, the National Board of Medical Examiners and the American Board of Allergy and Immunology. Since the publication of this article, Dr Lang has become the co-director of the Asthma Centre.

What kind of Research was this?
This research was conducted as a cross-sectional study, a type of observational study which allows variables in a sample population to be analysed. Typically, the participants of the research are similar in all variables, except the one that is being analysed. In this study, the sample population was selected based on the following criteria:


 * Clinic patients between the ages of 6 and 12 years old.
 * Who had visited the clinic in the preceding 2 years.

Asthma diagnosis, formed the differing variable within the cross-sectional study. This type of research allowed Lang et al, to observe the influence of asthma in a similar sample population, avoiding irrelevant data so that comparisons could be made.

It is important to note that data was collected via self-reporting, which is typically bias in nature. Further research monitoring the actual levels of physical activity in children should be undertaken.

What did the research involve?
From the selection criteria (listed above), 3001 patients were suitable for the study. From this sample, 357 patients with diagnosed asthma were selected, as well as 357 age-matched random controls.

After an introductory letter was sent to parents, it was determined that 342 of the asthma sample group were eligible for the survey, and 324 from the control group.

A 76 question survey was administered via telephone call, and addressed areas such as physical activity, asthma diagnosis, symptoms and medication. Asthma was defined using pre-existing criteria from the Centers for Disease Control and Prevention.

Physical activity was measured in 2 ways, the total number of days active in a typical week and the total minutes active in 1 day (preferably the previous day). A physical activity checklist was implemented to assist parents in recalling the child’s behaviour on the previous day.

A total of 243 were interviewed (137 asthma, 106 control).

Results were analysed using the data analysis tool, Strata 7.0, and comparisons were made between participants identified as control and asthma. To increase the accuracy of this study, the physical activity level of participants could have been monitored. The researchers based their analysis off the self-reporting of parents, who may not have been able to provide entirely accurate representations of the child’s level of physical activity for a given day, especially in circumstances where the parent was recalling a day where they were not with the child (e.g. a school day).

What were the basic results?


Using specific criteria, Lang et al, concluded that children suffering from asthma were less active than their counterparts. With a reported average of 116 minutes of physical activity a day for children with asthma, and 146 minutes for children in the control group (without asthma).

In addition, it was determined that 21% of children with asthma completed less than 30 minutes of activity a day, in comparison to 9% for those without asthma. Similarly it was reported that 23% of the asthma group were active less than 3 days a week, whereas only 11% of the control group were.

Lang et al, determined that the severity of asthma and the parental beliefs were strong predictors of physical activity levels. As those with severe asthma were more likely to be active for less than 30 minutes a day, and the children with parents who believed that exercise can improve asthma were more likely to be active for more than 120 minutes a day.

What conclusions can we take from this research?
This study provides strong evidence that, asthma contributes to the extent of which children are physically active in comparison to those who do not suffer from the disease.

Severity and parental beliefs acted as the most influential predictors of physical activity. This indicates that there is a lack of understanding surrounding asthma and the benefits of physical activity, and emphasises the need for better education for parents and caregivers surrounding exercise and the management of asthma.

In addition to parent education, it would be beneficial for intervention programs to be developed for children with asthma, in which exercises can be implemented which are appropriate for the severity of the child’s asthma so that EIA is not triggered.

Practical advice
Physical activity is linked to the onset of asthma attacks, so individuals who show symptoms of asthma should be encouraged to visit a health professional for proper diagnosis.

Physical activity provides numerous health benefits for individuals, and therefore asthma sufferers should not be restricted or refrain from exercising.