Exercise as it relates to Disease/How swimming helps children with asthma and other illnesses

This page is the critique of the journal article Effects of swimming training on aerobic capacity and exercise induced bronchoconstriction in children with bronchial asthma written by Matsumoto I et al.

What is the background to this research?

Asthma is quite a common condition due to chronic inflammation of the lower respiratory tract. Chronic lower airway inflammation is known to be more common in individuals that also have inflammatory disorders of the upper airway. Asthma is distinguished by chronic inflammation of the airways in which there is an accumulation of eosinophils, mast cells, and activated T helper lymphocytes. These inflammatory cells release facilitators that then trigger bronchoconstriction, mucus secretion, and remodelling.. Globally, over 300 million people suffer from asthma.

Despite the fact that exercise is a contributing factor to triggers one’s asthma/exercise induced asthma and exercise induced bronchospasm, there is an increase in evidence that regular exercise combined with aerobic and anaerobic conditioning, can reduce the frequency and severity of all. Swimming is a common pastime activity and competitive sport for those who suffer from respiratory issues such as asthma. Review of available studies and research show that swimming induces less bronchoconstriction compared to other sports.

Several studies have shown that people who suffer from asthma, and other respiratory issues,  can improve their quality of life by participating in physical conditioning programs. Swimming is widely accepted in the community and is the form of exercise that is most commonly prescribed to suffers of asthma and other respiratory issues as it does not trigger and aggravate the symptoms compared to land-based exercises.

This study is important as asthma effects many children in the world.

Where is the research from?

This research was published at the Fukuoka University in Japan. The Research undertaken was done by multiple people at two locations; I Matsumoto, H Araki, K Tsuda, H Odajima and S Nishima were apart of the Division of Paediatrics located at the National Minami Fukuoka Chest Hospital, and Y Higaki, M Tanaka, H Tanaka and M Shindo were apart of the Laboratory and Exercise Physiology, School of Physical Education.

I Matsumoto is the correspondent for this article. All researchers appear to be appropriate and have produced a factual article.

What kind of research was this?

This was a randomised test where the test subjects were randomly allocated to a training group or a control group. The test subjects did not differ with respect to age, height, pulmonary function, or frequency of acute asthma attacks. This present study was undertaken to determine whether swimming training improves aerobic capacity and whether this truly results in less asthmatic symptoms in the test subjects, and in less exercise induced bronchoconstriction or whether apparent protection from exercise induced bronchoconstriction is simply due to an increased exercise capacity.

What did the research involve?

16 children with asthma diagnosed according to the ATS criteria who had been admitted to hospital for treatment for asthma participated in the study. All had severe asthma when admitted to hospital and the asthma attacks were controlled by treatment as an impatient. None were prescribed oral steroids.. As mentioned previously, the 16 children were randomly allocated into a training group or control group with eight in each. Their asthma medication was not modified during the duration of this study. The study was performed during autumn when allergic stimuli were minimal and when the children were free from asthma or any respiratory issues.

The first tests conducted focused on determining the subject’s aerobic capacity. These included a cycling ergometer test and a swimming ergometer test which were conducted with a one-day interval between tests. The incremental cycle ergometer test started with 10-15W for four minutes. The workload was increased by 5-10W every four minutes until exhaustion. The incremental swimming ergometer test was performed in a heated indoor pool using a tethered swimming method. Subjects swam freestyle for two minutes, their position was kept constant, and a load was applied with a rope that was attached around their waist. The workload was initially 0.1-0.2kp and gradually increased  by 0.2kp every two minutes until exhaustion.. Heart rates were monitored, and blood lactate concentrations were measured to determine their lactate threshold. Their aerobic capacity was defined as the workload at their lactate threshold.

The evaluation of exercised induced bronchoconstriction (EIB) was performed using both the cycle and swimming ergometers using six-minute protocols. The workloads were set at 100%-175% of  their lactate thresholds. Forced expiratory volume in one second was measured immediately before exercise and again 5 and 15 minutes after. EIB was expressed as follows:

((pre-exercise – lowest post-exercise/pre-exercise) x 100)

What were the basic results?

The swimming training programs improved the aerobic capacity in all subjects significantly in the training group. In the training group, the workload increased by 0.26 (0.11)kp on average whereas in the control group, the increase was only 0.4 (0.11)kp. Similar results were shown in the cycle ergometer with an increase in aerobic capacity by 10.6 (4.5)W in the training group and by 3.8 (5.2)W in the control group.

What conclusions can we take from this research?

We can conclude that swimming can benefit children who suffer from asthma. By having an individualised program and setting the training intensity at 125% of the child’s aerobic capacity while increasing the intensity weekly, increase in aerobic capacity can be achieved with significant improvements. The increase in aerobic capacity resulted in a decrease in EIB when assessed before and after the training period. This and many other studies have provided evidence that swimming is very beneficial to children who suffer from asthma in many ways and can improve their overall quality of life.

Practical advice

For children suffering from asthma and other respiratory issues, the most appropriate actions to take would be:

•       Have an accredited swimming coach assess the child and make an individualised training program for them
•       Continue to take their medication
•       Train in a heated pool
•       Get advice from professionals in the industry
•       Train consistently
•       Be assessed weekly
•       Have a healthy and balanced diet

Further information/resources

• The effects of a swimming intervention for children with asthmaresp_1
• Swimming and Asthma Benefits and Deleterious Effects
• Swimming attendance during childhood and development of asthma: Meta-analysis

• Effects of swimming training on children with asthma
• Is Swimming the Best Exercise for Children with Asthma?
• Asthma and swimming