The twenty-metre shuttle-running test: a combined test for maximal oxygen uptake and exercise-induced asthma?

A maximal multistage ‘twenty-metre shuttle-running test' has already been developed to estimate maximaloxygen uptake (VO 2 max). This field test requires little equipment or expertise, can be performed simultaneously by several subjects, and is widely used in physical education lessons. The present study assessed the potential for this test to provoke exercise-induced asthma in 73 schoolboys, aged 15–16 years. Measurements of the forced expiratory volume in one second (FEV 1 ) were made at rest and 10 min after the twenty-metre shuttle-running test; exercise-induced asthma was defined as greater than a 10% fall in FEV 1 after exercise. The pupils achieved 73±19 shuttles (mean±SD) giving a VO 2 max of 47·0±5·3 m1 kg −1 min −1 . Exercise-induced asthma was documented in eight pupils (11%); two were known asthmatics who, despite taking pre-exercise B 2 agonist treatment, had sharp falls in FEV 1 (−25·4. and −25·6%); two had previously experienced occasional chest tightness or wheeze with exercise (−16·5 and −13·2% fall FEV 1 ); but four were asymptomatic, with no previous asthmatic symptoms (−20·0, −18·, −15·3 and −11·4% fall FEV 1 ). This study has demonstrated the potential of the twenty-metre shuttle-running test to provoke exercise induced-asthma, and may therefore be a useful clinical test to assess for exercise-induced asthma when an estimate of VO 2 max would also be helpful. Furthermore, physical education teachers should take basic precautions when using this test. For example, known asthmatics should be encouraged to take medication before exercise; simple measurements of lung function such as the peak expiratory flow rate should be made before and after exercise; and a B 2 agonist inhaler available if required.