Aerosol particle emission increases exponentially above moderate exercise intensity resulting in superemission during maximal exercise

Abstract

Significance Airborne transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or other pathogens is probably increased during indoor exercise, but data on the emission of aerosol particles by an exercising individual are lacking. Here, we report that aerosol particle emission increases on average 132-fold from 580 ± 489 particles/min at rest to 76,200 ± 48,000 particles/min during maximal exercise. Aerosol particle emission increases moderately up to an exercise intensity of ≈2 W/kg and exponentially at higher exercise intensities. These data not only explain SARS-CoV-2 transmissions during indoor group exercise but also can be used to design better targeted mitigation measures for physical activity indoors such as physical education in school, dance events during weddings, or high-intensity gym classes such as spinning.

The impact of COVID-19 lockdowns on physical activity amongst older adults: evidence from longitudinal data in the UK

“…In deciding whether to engage in physical activity amid the COVID-19 pandemic, older adults must weigh up the benefits and risks to their health. Whilst regular activity can reduce the risk of chronic disease, [2] mortality, [4] and deconditioning, [19] and help mitigate against complications from COVID-19; [31] activity conducted with others, especially in an indoor setting, increases the probability of exposure [32]. These trade-off determinations are everchanging and will depend on the infection rate and the presence of new variants.…”

“…To do this effectively, it is integral that measures are taken to minimise the risk of COVID-19 infection, and that activity remains accessible to those who wish to socially distance themselves, especially in the winter months when the climate makes outdoor activity less feasible. Firstly, to reduce the risk of transmission in premises hosting indoor physical activity, we recommend the use of air filtration devices, implementing regular airing breaks, and encouraging participants to test for COVID-19 before entry [32,35]. Secondly, we recommend that government officials, health experts, and media professionals promote the uptake of home workouts so those wishing to avoid group physical activity can be active in the winter -tutorial videos can be accessed online and often do not require any equipment [36].…”

Reconciling airborne disease transmission concerns with energy saving requirements: the potential of UV-C pathogen deactivation and air distribution optimization

“…With the COVID-19 pandemic, new hygienic concerns emerged and the importance of minimizing the risk of respiratory disease transmission in buildings was raised. Virus laden airborne aerosols, which are typically 1 µm in size and remain in suspension in the air after being produced by employees when speaking, coughing and sneezing [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15] have indeed been found to be one of the major transmission routes of the SARS-CoV-2 virus and other viruses [16][17][18][19][20][21][22][23][24][25][26]. The risk of transmission therefore correlates with the rate at which indoor air is replaced by 'clean' (outdoor or decontaminated) air by the building's ventilation system.…”

The Spread of Exhaled Air and Aerosols during Physical Exercise

“…The general physical behavior of aerosols in enclosed rooms and thus various opportunities to decrease the risk of transmission by optimizing ventilation and sanitizing the air have been examined in the literature [ 3 , 19 ]. Yet, the effect of physical stress, e.g., in gyms or medical facilities, on aerosol generation and spreading is still a subject of current research and has to be investigated in detail [ 20 , 21 , 22 ]. Parallel to the assessment of aerosol spreading and protective masks during physical stress, user satisfaction should also be investigated, as the use of face masks can affect user comfort and exertion.…”