Field and laboratory exercise challenges for identifying exercise-induced bronchoconstriction

Educational aims

1. To define necessary conditions for a successful exercise challenge.

2. To provide operational procedures for performing an exercise challenge in the laboratory or the field for the identification of exercise-induced bronchoconstriction.

3. To compare positive and negative attributes of each challenge.

4. To provide spirometric cut-off criteria for positive challenge tests.

Summary Exercise challenge tests are often used for identification of exercise-induced bronchoconstriction (EIB). Optimal test conditions are: absolute humidity of <10 mg H2O per L; exercise intensity resulting in a sustained increase in minute ventilation to 14–21 times the forced expiratory volume in 1 s or heart rate (HR) to 80–90% of the estimated maximal HR; and exercise duration of 6–8 min. Variability in fitness level and age necessitate individualisation of the exercise protocol. Field tests are subject to variability in test conditions and may have poorer repeatability than laboratory tests that require expensive equipment. However, either challenge test can be employed for the diagnosis of EIB in conjunction with a critical clinical assessment.