title: The effect of pre-exercise diesel exhaust exposure on cycling performance and cardio-respiratory variables.
abstract: OBJECTIVE
  To determine the effect of pre-exercise exposure to diesel exhaust (DE) on 20-km cycling performance, pulmonary function, and cardio-respiratory variables during exercise.
  
  
  METHODS
  Eight endurance-trained males participated in the study. Test days consisted of a 60-min exposure to either filtered air (FA) or DE, followed by a 20 km cycling time trial. Exposures to DE were at a concentration of 300 µg/m³ of PM(2.5). Forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were measured before and after exposure, and after exercise. Oxygen consumption (VO₂) and carbon dioxide production (VCO₂), minute ventilation (V(E)), tidal volume (V(T)), breathing frequency (F(B)), heart rate and oxyhemoglobin saturation (SpO₂), were collected during the time trials. The effect of condition on time trial duration, an order effect, and mean cardio-respiratory variables were each analysed using paired T-tests. Repeated-measures ANOVA were used to assess the effect of DE exposure on pulmonary function.
  
  
  RESULTS
  There was a main effect of condition (FA vs. DE) on the change in FEV₁ from baseline, and in exercise heart rate. Post hoc tests revealed that exercise-induced bronchodilation was significantly attenuated following DE compared to FA. There were no main effects of condition on 20 km cycling performance, or VO₂, VCO₂, V(E), V(T), F(B) and SpO₂ during a 20 km time trial.
  
  
  CONCLUSIONS
  A 60-min exposure to DE prior to exercise significantly attenuated exercise-induced bronchodilation and significantly increased heart rate during exercise. Pre-exercise exposure to diesel exhaust did not significantly impair 20 km cycling time trial performance.
authors.affiliation: School of Kinesiology, University of British Columbia, British Columbia, Canada. luisagiles@gmail.com
authors.forename: Luisa V
authors.initials: LV
authors.lastname: Giles
authors.forename: Christopher
authors.initials: C
authors.lastname: Carlsten
authors.forename: Michael S
authors.initials: MS
authors.lastname: Koehle
mesh_terms: D000328:Adult; D054874:Athletic Performance; D001642:Bicycling; D016085:Bronchoconstrictor Agents / Q000633:toxicity*; D002245:Carbon Dioxide / Q000378:metabolism; D002317:Cardiovascular Agents / Q000633:toxicity*; D002319:Cardiovascular System / Q000187:drug effects* / Q000378:metabolism; D018592:Cross-Over Studies; D015444:Exercise; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects; D010108:Oxyhemoglobins / Q000032:analysis; D052638:Particulate Matter / Q000633:toxicity; D012143:Respiratory Physiological Phenomena / Q000187:drug effects; D012137:Respiratory System / Q000187:drug effects* / Q000378:metabolism; D016037:Single-Blind Method; D001335:Vehicle Emissions / Q000633:toxicity*; D055815:Young Adult
chemical_list: D016085:Bronchoconstrictor Agents; D002317:Cardiovascular Agents; D010108:Oxyhemoglobins; D052638:Particulate Matter; D001335:Vehicle Emissions; D002245:Carbon Dioxide