This article presents an experimental study of the concentration of fine dust in a covered sports facility using the example of a sports gym using a HANDHELD-3016 aerosol particle counter. The monitoring data of indoor air was analyzed and graphically presented in graphs of the integral function of the distribution of dust particles over the diameters. The concentration of fine dust at different time intervals during the training of the sports section was compared. The dependence of the distribution of dust particles over the measurement heights on the intensity of the workout was studied. Recommendations on improving air quality in a sports-type room during classes were provided. Changes in the indicators of external respiration during the training session was analysed.