Changes Of Indoor Air Quality According To Exercise Types, Intensity, And Number Of Exercisers

Abstract

PURPOSE: The purpose of this study is to examine the changes in indoor air quality according to exercise types, intensity, and the number of exercisers. METHODS: Twelve college students (6 men: 20.8 ± 1.5 yrs, 74.8 ± 5.6 kg; 6 women: 21.0 ± 0.8 yrs, 56.9 ± 8.6 kg) participated in 3 testings; 1) a 16-meter shuttle run, 2) rhythmic rope skipping, and 3) soccer tricks (trapping, passing, and dribbling). In each testing, they exercised at 3 intensities according to the ACSM classification; low (LI: 57-63%), medium (MI: 64-76%) and high (HI: 77-95% of maximal heart rate). Each testing lasted for 80 min consisted of 20 min exercise at LI, 10 min resting, 20 min exercise at MI, 10 min resting, and 20 min exercise at HI. The ventilation system of the gym of 10 × 18 × 3.3 (594 m3) at 23-24 °C with 60-70% relative humidity was shut off. During testings, their HR was monitored. For examining the influence of the number of persons exercising, 4 and 8 participants were retested for the 16-meter shuttle run. Indoor air quality was measured (Kweather IAQ-SC, IAQ-CW1, Korea) continuously during the testings for PM10, PM2.5, CO2, and volatile organic compound (VOC). RESULTS: The average HR was ranged from 118-120, 136-142, and 155-170 bpm in LI, MI, and HI, respectively (p < 0.05). The PM10 and PM2.5 during shuttle run increased from 4.7 ± 0.2 and 3.5 ± .01 at baseline to 17.9 ± 0.7 and 11.3 ± 0.2 μg/m3 at the end, respectively (p < 0.01). During rope skipping, CO2 increased from 615.4 ± 24.5 to 1950.4 ± 56.3 ppm, and VOC increased from 16.4 ± 2.7 to 243.7 ± 55.4 ppb (p < 0.01). When comparing the number of exercisers, 12 was the greatest in both PM10 and PM2.5 (p < 0.01). CO2 was also the greatest during 12 exercisers as it changed from 792.6 ± 23.0 to 2123.2 ± 28 ppm (p < 0.01). VOC was the greatest during 4 exercisers as it changed from 6.6 ± 1.5 to 117.4 ± 2 ppb (p < 0.01). CONCLUSIONS: Physical activity such as shuttle run in a small gym evoked a most negative indoor dust particle quality. Rope skipping produced the most quantity of CO2 and VOC compared to other activity types. The more people exercise, the more air pollutants are produced. This work was supported by the Korea Sports Promotion Foundation (KSPO) and the Ministry of Culture, Sports and Tourism (MCST) of the Republic of Korea (No. S2020-04-02).