Physiological Responses to Acute Airborne Particle Exposure during Maximal Aerobic Power

The effect of the exposure to airborne particles on the physical performances achieved by athletes was investigated. Respiratory and cardiovascular parameters of nine subjects (volunteers, regularly performing physical activity) were measured during their high-intensity exercise performed indoor on a cycle ergometer. A steady-state concentration of airborne particles was generated through incense burning. Two different particle exposure scenarios were tested: low (no source in operation) and high exposure (particle generation from incense burning phenomena). Alveolar-deposited surface area doses received by subjects during low and high exposure tests were measured equal to 22.7 ± 8.58 and 1.18 ± 0.22 × 103 mm2, respectively. Oxygen uptake at the peak of the physical activity resulted statistically higher during high exposure tests, whereas lower peak heart rate values were measured for such scenario. In terms of mechanical efficiency, a higher peak metabolic power was recognized for subjects performing tests in high exposure conditions: results were statistically different (about 1%) with respect to low exposure tests. On the other hand, measurements of exhaled nitric oxide (parameter associated to airway inflammations) performed during the tests showed no significant differences between the two exposure scenarios