قرار گرفتن در معرض آلاینده های هوای داخل ساختمان هنگام فعالیت فیزیکی در مراکز تناسب اندام

ABSTRACT Exposure to indoor air pollutants during physical activity in fitness centers

According to the World Health Organization, physical inactivity was identified as the fourth greatest risk factor for mortality, accounting for 3.2 million deaths per year in the world [1]. Physical activity is an important factor for life quality and frequent practice of exercise, like walking or bicycling, presents great benefits for health [2]. A clean environment is also essential for human health and well-being. In Europe, the environmental aspect with most concern on human health is related to indoor and outdoor air pollution [3,4]. Considering these two aspects and in order to potentiate the benefits of physical activity, people who live in urban areas choose less polluted outdoor spots or fitness centers to avoid air pollution. In fact, athletes and the common individual can be at risk when they are practicing exercise in polluted environments due the fact that 1) the increase in the minute ventilation increases proportionally the quantity of inhaled pollutants; 2) most of the air is inhaled through the mouth, bypassing the normal nasal mechanisms for filtration of large particles and 3) the increased airflow velocity carries gaseous pollutants deeper into the respiratory tract [5].

Fitness centers present specific characteristics that can affect the indoor air quality (IAQ). Like in other indoor places, IAQ in gymnasiums is affected by building maintenance, building materials and type of ventilation, but what makes these places peculiar are the higher human occupancy and the type of activity developing inside. Fitness centers join all the conditions that promote the increase of CO2 concentrations because occupants are the dominant source of indoor CO2 and its production rate depends primarily on the number of people in the room and on their metabolic level [6]. Occupancy also has influence in the PM10 concentrations [7]. Branis and colleagues [8] observed a direct relation between the indoor concentrations of coarse PM and the number of children present in a scholar gymnasium. Also in school gyms, Buonanno [9] concluded that the high levels of coarse PM concentrations are produced by students’ activity.

Therefore, there is an indubitable higher exposure to air pollutants in gymnasiums not only due to the characteristics of these places but also due to the changes in the respiratory parameters caused by the physical activity. However, despite the importance of healthy air in sport facilities, IAQ studies have been focused principally on schools [10e18], elderly care centers [19e21]; homes [22] and offices [23]. Comparatively, IAQ monitoring programs carried out in sport facilities are very scarce. Aside from the studies of Buonanno [9] and Branis [8,24] performed in school gyms, only the exposure in ice rings are object of study since the 90’s due to the high levels of CO, NO2 and PM that are emitted by the ice resurface vehicles [25e27] and exposure in swimming-pools due to the high concentrations of trihalomethanes [28]. Some other works were conducted in fitness centers but their focus was energy consumption or thermal comfort [29e31]. This paper aims to conduct a comprehensive characterization of IAQ in fitness centers and to identify the principal sources that compromise IAQ. This evaluation will be useful for epidemiological studies and to develop appropriate control strategies not only to minimize the adverse health effects on exercise practitioners, but also to potentiate the benefits of the physical activity.