# Exercise as it relates to Disease/the effects of physical activity on children with asthma
### What is Asthma?

Asthma is a condition in that affects the airways. It is a condition in which the airways within the lungs are sensitive which causing the airways to narrow, resulting in difficulty to breathe when triggered.

### Causes of Asthma

There are three main causes that narrow the airways which include:
* Inflammation of the lining inside the airway
* Over production of mucus causing a blockage in the airway
* The tightening of the muscles around the airway known as bronchoconstriction

### Classification of Severity

The severity of asthma is classified into three categories which are mild, moderate and severe. The way in which they are classified is by measuring:
* Forced expiratory volume in 1 second (FEV1)
* Peak expiratory flow (PEF)
These values are expressed as percentage of a predicted normal value. On the basis of these predicted values the severity is classified.
* Mild - > 80%
* Moderate - >60% and < 80%
* Severe - < 60%

### Prevalence of Asthma

Compared to the rest of the world Australia has a high prevalence of asthma. It estimated that over 2 million people within Australia suffer from a form of asthma, with 1 in 9 children suffering from the condition. Over the last decade there has been a slight decrease in prevalence within children.

### Triggers of Asthma

Common triggers from the National Asthma Council of Australia include:
* respiratory infections, such as colds and flu
* cigarette smoke
* allergy-related triggers, e.g. house dust mites, pollen, pets or moulds
* weather, e.g. cold air, change in temperature, thunderstorms
* work-related triggers, e.g. wood dust, chemicals, metal salts
* irritating substances breathed in the air, such as bushfire smoke
* certain medicines, e.g. aspirin, some blood pressure drugs
* stress and high emotions, such as crying

## Why is Asthma an Issue in Children?

Asthma is a major health concern within children as it impedes their function in daily life. The shortness of breath caused by asthma tends to deter children from participating in physical activity. This deterrence of physical activities can lead be other lifestyle conditions such as social exclusion, impact self-esteem and effect the child’s development.

## Effects of Physical Activity on Asthma

Studies have proven that physical activity have beneficial effects on a variety of aspects of asthmatic children’s lives. These areas include pulmonary function, exercise capacity, behavioural aspects and quality of life.
Each of the areas have a flow on effect to each other. By participating in regular physical activity each week studies have found that children’s pulmonary function increases which leads into having a greater exercise capacity. With this increased capability children’s deterrence of participating will be lowered as they are able to be physically active without being restricted by their airways. By participating in in team sports children have increased physiological benefits that lead positive influences in behavioural aspects and quality of life.
A form of physical activity which has substantial benefits for children with asthma is swimming. Swimming has great benefits because of the warmer air located near the surface of the water. This air is easier to breathe and can help a person increase volume capacity within the lungs and help develop good breathing techniques.

## Recommendations for Children with Asthma

The following recommendations are from the National Asthma Handbook in relation to the effects of physical activity with children with asthma. These include:
* Physical activity for should be incorporated into everyday life as it is beneficial on the effect of their quality of life.
* Educating children and parents who suffer from asthma that physical activity and exercise does not need to be avoided and the benefits of participating in such activities.
* Exercise-induced bronchoconstriction can be managed effectively and should not be a reason to avoid physical activity.
* Children involved in sport should have an asthma action plan in place in case of an emergency

## Further reading

* Asthma Australia
* National Asthma Council Australia
* Australian Asthma Handbook

## References

* 1 2 Asthma Australia, 2014. What is Asthma?. [Online] Available at: http://www.asthmaaustralia.org.au/What_is_asthma.aspx
* 1 2 Sawyer, G., Miles, J., Lewis J, F. P. & Pearce, N. B. R., 1998. Classification of asthma severity: should the international guidelines be changed?. Clinical and Experimental Allergy, Volume 28, p. 1565–1570.
* 1 2 National Asthma Council Ltd, 2014. National Asthma Council Australia - Asthma Facts. [Online] Available at: http://www.nationalasthma.org.au/understanding-asthma/asthma-facts
* ↑ National Asthma Council Ltd, 2014. Symptoms and Triggers. [Online] Available at: http://www.nationalasthma.org.au/understanding-asthma/symptoms-triggers
* 1 2 Veldhoven, N. H. v. et al., 2004. Children with asthma and physical exercise: effects of an exercise programme. Clinical Rehabilitation, Volume 15, pp. 360-370.
* 1 2 Basaran, S. et al., 2006. Effects of Physical Exercise on Quality of Life, Exercise Capacity and Pulmonary Function in Children with Asthma. J Rehabil Med, Volume 38, pp. 130-135.
* ↑ Lucas, S. R. & Platts-Mills, T. A. E., 2005. Physical activity and exercise in asthma: Relevance to etiology and treatment. J ALLERGY CLIN IMMUNOL.
* 1 2 Walters, J. A., 2014. Swimming training benefits children and adolescents with asthma: results of a systematic review. [Online] Available at: http://www.thoracic.org.au/imagesDB/wysiwyg/SundayWF11530-JuliaWalters-O-020.pdf
* ↑ National Asthma Council Australia, 2014. Physical Activity and Asthma. [Online] Available at: http://www.asthmahandbook.org.au/clinical-issues/exercise/physical-activity