Investigating performance and lung function in a hot, humid and ozone-polluted environment

Abstract

Large urbanized areas, where sports events take place, have a polluted environment and can also reach high temperatures and humidity levels. The aim of this study was to investigate the impact of a hot, humid and ozone-polluted (O(3)) environment on (1) performance of an 8 km time trial run, (2) pulmonary function, and (3) subjective respiratory symptoms in endurance-trained runners. Using crossover randomized design, 10 male participants (mean V(O)₂(max)= 64.4 mlO(2) kg(-1) min(-1), SD = 4.4) took part in a time trial run under four different conditions: 20 degrees C + 50% relative humidity (rh) (Control), 20 degrees C + 50% rh + 0.10 ppm O(3) (Control + O(3)), 31 degrees C + 70% rh (Heat), 31 degrees C + 70% rh + 0.10 ppm O(3) (Heat + O(3)). Heart rate, ratings of perceived exertion and minute ventilation were collected during the run. Lung function was measured pre and post-exercise. The runners completed a respiratory symptoms questionnaire after each trial. The completion time of both the Heat (32 min 35 s) and Heat + O(3) (33 min 09 s) trials were significantly higher (P < 0.0001) when compared to the Control + O(3) (30 min 27 s) and Control (30 min 15 s) trials. There were no significant changes between pre/post lung function measures or between trials. The effective dose of ozone simulated in the present study did not affect the performance and therefore, ozone-pollution, at an environmentally relevant concentration, did not compound the impairment in performance beyond that induced by a hot, humid environment.

Impact of heat and pollution on oxidative stress and CC16 secretion after 8 km run

“…Ozone alone did not significantly affect these variables. No differences, between trials, were observed for average heart rate (for detailed descriptions of these results please see Gomes et al 2010).…”

“…Two out of the ten runners presented hay fever as an allergic problem, however as this study was conducted during the autumn and winter period, this did not interfere with the participants' health. In addition, when the runners' pre and post lung functions were analyzed, it was seen that none of them presented EIB (Gomes et al 2010). …”

Effect of vitamin supplementation on lung injury and running performance in a hot, humid, and ozone‐polluted environment

“…Blood samples, nasal lavage, and lung function tests were performed again immediately post‐exercise and 6 h after the exercise. In addition, immediately post‐exercise, the runners completed a questionnaire rating the severity of their respiratory symptoms (Gomes et al., ). The subjects were asked to write down the food they consumed during the first exercise trial day and to repeat this intake during the next trial.…”

Diurnal physiological and immunological responses to a 10-km run in highly trained athletes in an environmentally controlled condition of 6 °C

“…Airway inflammation can be detected by an increase in inflammatory markers, such as neutrophils, macrophages, inflammatory cytokines and Clara cell protein (CC16) (Bonsignore et al 2001). CC16 is a biomarker of airway respiratory stress (Gomes et al 2010). This protein, initially described in the epithelium of the tracheobronchial tree as a secretory product from non-ciliated Clara cells, diffuses passively from the respiratory tract into plasma and is excreted via the urinary tract (Bernard et al 1997).…”

“…The functions of Clara cells are mainly oriented to the protection of the respiratory tract, decreasing inflammation of the airways and protecting the respiratory tract against oxidative stress (Gomes et al 2010). Also, CC16 found in plasma has been shown to be a sensitive marker for the early detection of increases in the permeability of the lung epithelial barrier (Hermans and Bernard 1999).…”