The effect of sustained heavy exercise on the development of pulmonary edema in trained male cyclists

To determine whether intense, prolonged activity can induce transient pulmonary edema, eight highly trained male cyclists (mean ± S.D.: age, 26.9 ± 3.0 years; height, 179.9 ± 5.7 cm; weight, 76.1 ± 6.5 kg) performed a 45-min endurance cycle test (ECT). V˙O2,max was determined (4.84 ± 0.4 L min−1, 63.7 ± 2.6  ml min−1 g−1) and the intensity of exercise for the ECT was set at 10% below ventilatory threshold (∼76% V˙O2,max 300 ± 25 W). Pre- and post-exercise pulmonary diffusion (DLCO) measurements and magnetic resonance imaging of the lung were made. DLCO and pulmonary capillary blood volume (VC) decreased 1 h post-exercise by 12% (P = 0.004) and 21% (P = 0.017), respectively, but no significant change in membrane diffusing capacity (DM) was found. The magnetic resonance scans demonstrated a 9.4% increase (P = 0.043) in pulmonary extravascular water 90 min post-exercise. These data support the theory that high intensity, sustained exercise in well-trained athletes can result in transient pulmonary edema.