Effect of exhaustive exercise on human neutrophils in athletes

In order to investigate the effect of exercise on the capacity of neutrophi ls to produce reactive oxygen species (ROS), eight male cross-country skier s underwent maximal exercise. Peripheral blood samples were taken pre-exerc ise, 0 h, 1 h, and 2 h after finishing maximal exercise. Leukocyte counts s ignificantly increased (p < 0.05), particularly lymphocytes (p < 0.05), jus t after the exercise period (0 h) and significantly increased again (p < 0. 05), particularly neutrophils (p < 0.05), 2 h after the exercise compared w ith pre-exercise values. The capacity of isolated neutrophils to produce RO S was assessed by lucigenin (Lg)-dependent chemiluminescence (CL) and lumin ol (Lm)-dependent CL on stimulation with opsonized zymosan (OZ) and phorbol myristate acetate (PMA). Just after exercise, the LgCL response was not af fected, while the response of LmCL mixed with sodium azide, which inhibits catalase and myeloperoxidase (MPO) activity, was significantly enhanced (p < 0.05). In addition, just after exercise, the level of serum growth hormon e increased significantly (p < 0.05). The serum cortisol level also increas ed significantly just after and 1 h after exercise (p < 0.05). These data i ndicated that maximal exercise not only mobilized neutrophils from marginat ed pools into the circulation, but also caused increased ROS generation. Co pyright (C) 2000 John Wiley & Sons, Ltd.