Luisa V Giles1, Jason P Brandenburg, Christopher Carlsten, Michael S Koehle. 1. 1School of Kinesiology, University of British Columbia, British Columbia, CANADA; 2Department of Kinesiology, University of the Fraser Valley, British Columbia, CANADA; 3Department of Medicine, University of British Columbia, British Columbia, CANADA; 4School of Population and Public Health, University of British Columbia, British Columbia, CANADA; and 5Division of Sports Medicine, University of British Columbia, British Columbia, CANADA.
Abstract
BACKGROUND: Outdoor exercisers are frequently exposed to diesel exhaust (DE) that contains particulate matter (PM) air pollution. How the respiratory and metabolic responses to exercise are affected by DE exposure and how these responses change with exercise intensity are unknown. PURPOSE: This study aimed to determine the respiratory and metabolic responses to low- and high-intensity cycling with DE exposure containing high levels of PM. METHODS: Eighteen males age 24.5 ± 6.2 yr performed 30-min trials of low-intensity (30% of power at V˙O2peak) and high-intensity (60% of power at V˙O2peak) cycling as well as rest. Each trial was performed once while breathing filtered air (FA) and once while breathing DE (300 μg·m of PM2.5) for a total of six trials, each separated by 7 d. During the trials, minute ventilation (V˙E), oxygen consumption (V˙O2), CO2 production (V˙CO2), RER, and perceived exertion for lungs (RPELungs) and legs (RPELegs) were measured. Work of breathing, respiratory muscle V˙O2, ratio of O2 consumption to power output, and gross efficiency were estimated. RESULTS: The RER was significantly lower (0.02 lower, P = 0.008), and the RPELungs (0.9 greater, P = 0.001) and the RPELegs (0.6 greater, P = 0.017) were significantly greater, in DE compared with FA. During low-intensity exercise, V˙E (44.5 ± 8.9 vs 40.5 ± 8.0 L·min, P < 0.001), V˙O2 (27.9 ± 5.4 vs 24.9 ± 4.4 mL·kg·min, P = 0.001), and V˙CO2 (25.9 ± 5.3 vs 23.5 ± 4.5 mL·kg·min, P = 0.006) were significantly greater in DE. This pattern was not seen during high-intensity cycling. CONCLUSIONS: Respiratory and metabolic responses to low-intensity, but not high-intensity, cycling in DE exceed FA. Practically, the greater responses during low-intensity exercise in DE could have implications for individuals with cardiopulmonary disease. Also, the elevated RPE during DE could impair performance in self-paced exercise.
BACKGROUND: Outdoor exercisers are frequently exposed to diesel exhaust (DE) that contains particulate matter (PM) air pollution. How the respiratory and metabolic responses to exercise are affected by DE exposure and how these responses change with exercise intensity are unknown. PURPOSE: This study aimed to determine the respiratory and metabolic responses to low- and high-intensity cycling with DE exposure containing high levels of PM. METHODS: Eighteen males age 24.5 ± 6.2 yr performed 30-min trials of low-intensity (30% of power at V˙O2peak) and high-intensity (60% of power at V˙O2peak) cycling as well as rest. Each trial was performed once while breathing filtered air (FA) and once while breathing DE (300 μg·m of PM2.5) for a total of six trials, each separated by 7 d. During the trials, minute ventilation (V˙E), oxygen consumption (V˙O2), CO2 production (V˙CO2), RER, and perceived exertion for lungs (RPELungs) and legs (RPELegs) were measured. Work of breathing, respiratory muscle V˙O2, ratio of O2 consumption to power output, and gross efficiency were estimated. RESULTS: The RER was significantly lower (0.02 lower, P = 0.008), and the RPELungs (0.9 greater, P = 0.001) and the RPELegs (0.6 greater, P = 0.017) were significantly greater, in DE compared with FA. During low-intensity exercise, V˙E (44.5 ± 8.9 vs 40.5 ± 8.0 L·min, P < 0.001), V˙O2 (27.9 ± 5.4 vs 24.9 ± 4.4 mL·kg·min, P = 0.001), and V˙CO2 (25.9 ± 5.3 vs 23.5 ± 4.5 mL·kg·min, P = 0.006) were significantly greater in DE. This pattern was not seen during high-intensity cycling. CONCLUSIONS: Respiratory and metabolic responses to low-intensity, but not high-intensity, cycling in DE exceed FA. Practically, the greater responses during low-intensity exercise in DE could have implications for individuals with cardiopulmonary disease. Also, the elevated RPE during DE could impair performance in self-paced exercise.
Authors: Stephanie DeFlorio-Barker; Danelle T Lobdell; Susan L Stone; Tegan Boehmer; Kristen M Rappazzo Journal: Prev Med Date: 2020-07-09 Impact factor: 4.018
Authors: Shichun Huang; Huan Feng; Shanshan Zuo; Jingling Liao; Mingquan He; Masayuki Shima; Kenji Tamura; Yang Li; Lu Ma Journal: Int J Environ Res Public Health Date: 2019-06-26 Impact factor: 3.390
Authors: Luisa V Giles; Michael S Koehle; Brian E Saelens; Hind Sbihi; Chris Carlsten Journal: Environ Health Prev Med Date: 2021-06-30 Impact factor: 3.674
Authors: Lauren H Wyatt; Robert B Devlin; Ana G Rappold; Martin W Case; David Diaz-Sanchez Journal: Part Fibre Toxicol Date: 2020-11-16 Impact factor: 9.400