The effect of ipratropium bromide on maximal exercise capacity in asthmatic and non-asthmatic men

The effect of 0.5 mg nebulized ipratropium bromide (IB) on the cardio-respiratory responses to a progressive maximal cycle exercise test was compared with a matched placebo (P) in eight mild asthmatic and eight non-asthmatic men. The forced expiratory volume in l s (FEV1) in the asthmatic group was higher after ipratropium bromide both at rest [IB, mean 4.07 (SD 1.18) l versus P, 3.83 (1.29) l, P less than 0.05] and after exercise [IB, 3.64 (1.31) l versus P, 3.30 (1.40) l, P less than 0.02]. Since the percentage fall in the FEV1 after exercise was not significantly changed by ipratropium bromide [IB, -12 (11)% versus P, -16 (14)%], the improvement in the post-exercise FEV1 in the asthmatic group is attributable to the pre-exercise bronchodilatation. The resting and post-exercise FEV1 in the non-asthmatic group were also significantly higher after ipratropium bromide. However, neither group showed any differences in the cardio-respiratory, haemodynamic or subjective responses to the progressive maximum exercise test when ipratropium bromide was compared with placebo. These results demonstrate the absence of significant cardio-respiratory effects during exercise with this relatively high dose of ipratropium bromide, in patients with mild asthma and in non-asthmatic subjects. No ergogenic effect on maximal exercise performance was shown to question its use by asthmatic athletes engaged in high level competition.