间歇性低氧暴露期间运动对体育系大学生脑血流速度的影响

目的:探讨不同低氧暴露期间运动对人体脑血流速度的影响.方法:以6名体育系男性大学生为实验对象,采用经颅多普勒技术测试了其在4周实验期内,常氧(21% O2)、急性低氧暴露(15.4%O2)和慢性间歇性低氧暴露(15.4%O2)运动时脑中动脉血流速度.结果:常氧环境中运动可以增加脑血流速度.急性和慢性间歇性低氧暴露时,运动虽然也能提高脑血流速度,但增加幅度明显小于常氧环境.急性和慢性间歇性低氧暴露时,运动会降低舒张期血流速度.随着低氧暴露刺激时间的延长,脑血流速度的变化特点与幅度逐渐与常氧时一致.低氧暴露对运动后脑血流的恢复速度影响不大.

Effect of Intermittent Hypoxic Exposure with Exercise on Cerebral Blood Flow Velocity in College PE Students

The aim of this study was to investigate the effect of different duration of hyp oxic exposure with mild exercise on the velocity of cerebral blood flow (CBF). Methods Six male college students from department of PE exerci sed at the same relative percentages of peak oxygen uptake for 20 minutes at nor moxia, on acute hypoxic exposure and during chronic hypoxic intermittent exposur e in normal baric-hypoxic laboratory. The velocity of cerebral blood flow was me asured by Transcranial Doppler(TCD) technique at rest,during and after exercise on a bicycle ergometer. Results The v elocity of cerebral blood flow increased under normoxia. The velocities of CBF d uring exercise under acute and chronic intermittent hypoxia were also increased, whereas the amplitude is significantly less than that under normoxia. End diast olic velocity (Vd) during exercise were reduced during acute and chronic intermi ttent hypoxic exposure. Hypoxic exposure had little effect on the recovering vel ocity.