Effects Of VOCs Inhalation During An Accute Step Exercise On Pulmonary Functions

Abstract

PURPOSE: The purpose of this study was to examine the effects of volatile organic compounds (VOCs) inhalation during an acute step exercise on pulmonary functions. METHODS: Nine healthy collegiate men (22.3±1.9 yrs, 177.5±5.1 cm, 77.2±7.1 kg, 24.5±1.6 kg/m2) participated in two experiments either at normal air (NA) or polluted air (PA) condition. In each session, subjects rested at a normal air (22-23°C, 45-65% relative humidity) for at least 15 min, then entered in an environmental chamber where the air was maintained either normal (20±1, 1227±1063, <250, and <120) or polluted (48±1 μg/m3 of PM, 2487±445 ppm of CO2, >500 μg/m3 of VOCs, and >120 μg/m3 of HCHO). During the exposure, they rested for 30 min, and then performed a 10-min bout of step exercise at approximately 80% of individual maximal heart rate followed by 15 min recovery. The exercise consisted of 40 cm height block stepping at 30 repetition per min using a metronome. Before the exposure, at the end of resting, immediately after the exercise, and the last minute of recovery, pulmonary functions such as functional vital capacity (FVC), forced expiratory volume in one sec. (FEV1), and forced expiratory flow (FEF25-75%), peak expiratory flow (PEF), and blood pressure (BP) were measured. Heart rate (HR) were monitored and recorded continuously during the experiments. Blood lactate was measured using a finger prick method before and after the exercise. RESULTS: FVC before exercise was 5.09±0.43 in NA and 5.39±0.39 liter in PA while that at the end of exercise was 5.43±0.69 in NA and 5.82±0.84 liter in PA (p>0.05). No differences between NA and PA in any measurement time were found in FEV1, FEF25-75%, and PEF. BP and HR were not different between conditions. Blood lactate before exercise was 2.2±0.4 and 2.3±0.6 mmol/L in NA and PA, respectively (p>0.05), but that at the end of exercise was 6.9±2.5 and 8.9±1.7 mmol/L in NA and PA, respectively (p<0.05). CONCLUSIONS: No differences in measured pulmonary functions between NA and PA were observed during a short bout high intensity exercise while breathing VOCs. However, aerobic capacity may be restricted due to VOCs breathing and an individual variability was noticed. (This research project was support by the Korea Sport Promotion Foundation from Ministry of Culture, Sports and Tourism, Korea, Kookmin Univ. contract #20090274)