[The measurement of airway resistance during exercise by body plethysmography before and after application of asthma-protective drugs (author's transl)].

The behaviour of airway resistance under and after physical exercise up to 75 watt was investigated in 70 persons. In this test the airway resistance of subjects with healthy lungs and patient suffering from bronchial hyperreactivity does not show any significant changes. Patients with manifest obstructive ventilation disorders may be divided into two groups: in the major group (preponderant patients with a chronic bronchitis) the airway resistance decreases under exercise and reaches not the starting level up to the 8th minute after finishing exercise. In the minor group with the clinical picture of asthma the airway resistance increases during and after exercise and reaches it maximum in the 4th minute of recreation. In the same group the oxygen partial pressure decreases under exercise but on the average remains within the age-dependent reference-range. With the drugs disodium cromoglycate ("Intal"), Ketotifen ("Zaditen") and ipratropium bromide ("Atrovent") it's possibly to reduce the exercise induced increase of airway resistance; in comparison ipratropium bromide has the best effect.