Free running test for exercise-induced bronchospasm.

The free running test has been successfully carried out in patients from 5 to 21 years old. It has the following advantages: (1) it simulates normal exercise pattern; (2) it is readily performed in any health care setting; (3) it is simple to perform and noninvasive in nature; and (4) it reveals a maximum decrease in forced expiratory volume at one second at five minutes after the exercise period. There seems to be a seasonal variation that may alter outcome of tests.