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目的 探讨高原人体运动前后血流动力学的变化及高压氧预处理(hyperbaric oxygen preconditioning,HBOP)的影响,为改善高原劳动能力寻求新的措施.方法 6名由平原入伍进驻到海拔3800m高原地区6～24个月的健康男性战士自愿参与实验研究,用心-血管动力监控仪分别对受试对象在HBOP前和预处理5、7d后安静时,运动5 min以及运动后恢复3 min时的每搏输出量(stroke volume,SV)、左室射血时间(left ventricular ejection time,LVET)、心率(heart rate,HR)、逐次心跳间期(inter-beat interval,IBI)和心输出量(cardiac output,CO)等血流动力学指标进行记录分析.结果 HBOP7 d体力负荷5 min时的SV[(110.32±11.99) ml]较同状态下无HBOP的对照值[(85.08±23.48) ml]显著增加,差异具有统计学意义(P＜0.05);HBOP5 d运动后恢复3 min时LVET[(267.24±13.62) ms]较对照组[(243.79±11.56)ms]显著延长,差异具有统计学意义(P＜0.05);同时,HBOP后IBI延长、HR减慢,CO有增加的趋势,但与对照值比较均不具有统计学意义(均P＞0.05);经HBOP 7 d后各指标较HBOP5 d时未见显著变化(P＞0.05).结论 机体在高原低氧环境下体力负荷时心肌收缩力降低,心脏泵血功能受到抑制,HBOP能通过改善机体血流动力学提高心脏储备能力,增强高原缺氧环境下的心-血管功能,从而改善高原战士的劳动能力,而且经HBOP5 d即可达到改善血流动力学的目的,效果与HBOP7 d差异无统计学意义.“,”Objective To investigate changes in hemodynamics both before and after physical exercise and the protective effects of hyperbaric oxygen preconditioning (HBOP) on the soldiers,so as to find out new measures for enhancement of human physical performance at high plateau regions.Methods Six healthy male soldiers who used to live in the plain region,joined the army,and moved to the high plateau at an altitude of 3 800 m 6 to 24 months ago were voluntarily enrolled for our study.Such hemodynamic parameters as stroke volume (SV),left ventricular ejection time (LVET),heart rate (HR),inter-beat interval (IBI) and cardiac output (CO) before HBOP and after 5-day and 7-day HBOP and at rest,as well as at 5-minute exercise and 3 minutes after exercise,were recorded and analyzed by using the cardiovascular dynamic monitor.Results The stroke volume detected at 5-minute physical load following 7-day HBOP was significantly increased[(110.32 ± 11.99)ml],as compared with the control value[(85.08 ± 23.48)ml],with statistical significance (P ＜ 0.05),while left ventricular ejection time was significantly prolonged [(267.24 ± 13.62) ml],as compared with the control value[(243.79 ± 11.56) ml],also with statistical significance (P ＜ 0.05).inter-beat interval was prolonged,HR decreased and CO increased,following HBOP,but there was statistical significance,when comparisons were made with those of the control values (P ＜ 0.05).No significant changes in the levels of various parameters could be seen,after 7-day HBOP,as compared with the levels of the parameters after 5-day HBOP.Conclusions Myocardial contraction was decreased at acute hypoxia and with physical load and cardiac output was also obviously reduced.HBOP could increase potential cardiac output through improvement of hemodynamics and enhance cardiovascular function at acute hypoxia,thus increasing the physical performance of the soldiers at high plateau regions.Furthermore,5-day HBOP could achieve the goal of improving hemodynamics.