Project leader: Michael Koehle

The project objectives are to investigate the effects of short-duration diesel exhaust-exposure during exercise on respiratory function and to assess the effects of IBA (Inhaled Beta Agonist, or commonly known as an inhaler) use in the treatment of respiratory symptoms and impaired lung function due to diesel exhaust-exposure immediately following inhalation and two hours following inhalation, when the “bronchodilating” (the opening up of lung passageways) effects of IBA and exercise begin to wear off.

In a double-blind, randomly-assigned, repeated-measures crossover design, twenty asthmatics exercised on a stationary bicycle while breathing either filtered air or diesel exhaust following the inhalation of either a placebo (air) or IBAs. Asthmatics were exposed to the four exposure conditions (filtered air - IBAs, filtered air - placebo, diesel exhaust - IBAs, diesel exhaust - placebo) and performed a 30-min constant workload exercise test at 50% of peak cycling resistance achieved on the screening day on a cycle ergometer.

Based on preliminary findings, the research team has concluded that breathing increased levels of diesel exhaust during submaximal cycling may reduce the bronchodilatory response to exercise in asthmatics with no corresponding sensory consequences. An addition project result showed that thirty minutes of submaximal, constant-intensity cycling exercise appears to positively affect inhibitory control, attention and information processing speed, even when breathing increased levels of diesel exhaust.