Mucociliary clearance in healthy men at rest and during exercise.

We measured mucociliary clearance at rest and during exercise in 11 healthy non-smoking men. The subjects inhaled an aerosol containing [99Tcm]albumin millimicrospheres with deep inhalations. Four sets of scintigraphic images were obtained with 15-min intervals. Lung retention of radioactivity was quantified using a gamma camera and the clearance of particles from the lungs calculated for each 15-min period. The first image was obtained directly after inhalation, the second after a period of 15-min rest, the third after a period of exercise on a bicycle ergometer (workload approximately 80% of predicted maximum capacity) and the final fourth image after another period of rest. We found small differences in clearance rate at rest and during exercise indicating that there is no substantial change in the clearance rate during exercise in normal subjects.