Swimming and asthma – well tolerated and beneficial, finds new review

Key message: swimming training is well tolerated in children and teens with asthma and increases physical fitness and lung function.  However, it is not known whether this is better and/or safer than other types of physical activity.

We’re putting the spotlight on asthma today. It’s World Asthma Day and the Cochrane Airways Group has just published a new review on swimming training for asthma. World Asthma Day aims to spread the message “you can control your asthma” and this year activity organizers are being encouraged to complete the sentence “It’s time to…” So does this new review suggest that we could finish that sentence with “swim”?

Eight randomized controlled trials (RCTs) were included in the review, with 262 people aged five to eighteen years, who had stable asthma ranging from mild to severe. One RCT evaluated a programme of 30 minutes swimming six times a week; the rest involved swimming from 30 to 90 minutes two to three times a week, for six to twelve weeks. Swimming training was compared with golf in one study and ‘usual care’ in the other studies.

What did they find?

• No difference between groups for the primary outcomes of interest: quality of life (one study of 50 people, swimming compared with golf), asthma control, asthma exacerbations or use of corticosteroids
• Swimming training had a clinically meaningful effect on exercise capacity compared with usual care
• Swimming training was associated with small improvements in resting lung function tests
• There were no adverse effects on asthma control

How good was the evidence and what are the gaps?

• The strength of the evidence (using the GRADE criteria) is low for quality of life and asthma control, moderate for urgent asthma visits to a doctor or lung function, and high for exercise capacity
• Data were limited – only a small number of participants overall and 42 withdrew early
• The 3 RCTs with high withdrawal rates were rated as being at high risk of bias; the other studies were rated as being at low risk of bias
• Swimming pool chlorination status was not reported in 4 studies; no studies reported bronchodilator use or time off school or work
• The reviewers’ attempts to obtain missing data were unsuccessful
• Studies with longer follow-up periods are needed to determine long term effects

Last year, a Cochrane review evaluating evidence on any sort of physical training for asthma found that it brought short-term improvements in fitness and that, as with swimming, it was well tolerated by people with stable asthma and should be encouraged. You can read more in the blog from The Lifestyle Elf here.

What this review can’t say is whether swimming is better, or safer, than other forms of physical training. But it seems reasonable to say that “it’s time to get active” and if you like to swim then you can enjoy the benefits without fear of aggravating your symptoms. If you are on Twitter and want to follow tweets from World Asthma Day, the hashtag is #WAD2013.

Links:

Beggs S, Foong YC, Le HCT, Noor D, Wood-Baker R, Walters JAE. Swimming training for asthma in children and adolescents aged 18 years and under. Cochrane Database of Systematic Reviews 2013, Issue 4. Art. No.: CD009607. DOI: 10.1002/14651858.CD009607.pub2.

Cochrane summary and podcast of this review http://summaries.cochrane.org/CD009607/swimming-training-for-asthma-in-children-and-adolescents-aged-18-years-and-under

Chandratilleke MG, Carson KV, Picot J, Brinn MP, Esterman AJ, Smith BJ. Physical training for asthma. Cochrane Database of Systematic Reviews 2012, Issue 5. Art. No.: CD001116. DOI: 10.1002/14651858.CD001116.pub3.

Cochrane summary and podcast of this review http://summaries.cochrane.org/CD001116/physical-training-for-asthma

The Lifestyle Elf. Exercise is good for asthmatics too. May 23rd 2012.

Swimming improves fitness in children with asthma BMJ 2013;346:f2714