The estimates of the risk of infection were provided for two different exercises: endurance (1 h) and resistance (0.45 h). The intensity levels of the two exercises are reported in Fig. 5. Both the exercises were carried out in a 315 m3 gym room. Simulations were performed considering one infected subject for both the exercises; all the subjects (infected and exposed) were considered breathing during the exercise. The infection risk was calculated for both cases (endurance and resistance training) considering each tested subject once as infected and calculating the risk of infection for a simultaneous exercising subject with the median minute ventilation. As a comparison, the infection risk was also calculated for a passive non-exerciser present in the room during the exercise. The infection risk increase factors are calculated by dividing the individual infection risks through the infection risk of a non-exerciser present in the same setting when the infected person is also a passive non-exerciser, which is considered as the lower baseline.
RNA copy concentrations, dose received by exposed subject, and their individual risk were evaluated for different air exchange rates, ranging from 0.5 [typical of room not equipped with mechanical ventilation systems (46 (link))] to 101/h.