Fig 1.
Laminar airflow ventilation system comprising an air supply unit and an exhaust unit.
The air supply unit ensures high-efficiency particulate air (HEPA)-filtered vertical airflow from over the runner’s head, whereas the exhaust unit draws contaminated air into the treadmill board. A booth encloses all three sides except for the entrance to the treadmill to maintain the laminar flow. The air sanitized by the HEPA filter in the exhaust unit is vented outside the booth.
Fig 2.
Performance of the laminar airflow ventilation system (LFVS) using artificial droplets.
(A and B) The airflow was observed using an airflow indicator tube located at a position assumed to be the breathing. (C–F) The four types of vertical airflow, including (C) not-activating the LFVS, D: activating only the exhaust unit (Exhaust ON), (E) activating only the air supply unit (Supply ON), (F) activating the two units (Supply and Exhaust ON).
Fig 3.
Airborne particulates generation during exercise.
(A) Representative graphs of the concentration of airborne particulates (<0.3 μm; red dots), sweat lactate (blue dots) levels, and heart rate (gray dots) during exercise. (B) Changes (Δ) from the warm-up in the number of airborne particulates (>0.3 μm; n = 10). #p<0.01, ##p<0.001 compared with the warm-up. LT, lactate threshold; 85%_1, the first half of the constant-load exercise at 85% of the expected maximum heart rate; 85%_2, the latter half of the constant-load exercise at 85% of the expected maximum heart rate.
Table 1.
Baseline characteristics of patients.
Table 2.
Airborne particulate generation during exercise.
Fig 4.
Airborne particulate generation during anaerobic exercise using the laminar airflow ventilation system (LFVS).
(A) Representative graphs of the concentration of airborne particulates (<0.3 μm) (red dots) in activating the LFVS during constant exercise 4 minutes after reaching 85% of the expected maximum heart rate. (B) Concentration of airborne particulates (>0.3 μm) before and after the activation of the LFVS (n = 10). ##p<0.001 compared with the off LFVS, 85%, constant-load exercise at 85% of the expected maximum heart rate, LT, lactate threshold.
Table 3.
Airborne particulate generation during anaerobic exercise using the laminar airflow ventilation system (LFVS).