海拔和劳动负荷对摄氧量和心率的影响

Altitude and Physical Workload Combination Effect on Oxygen Uptake and Heart Rate

目的探究不同海拔和劳动负荷对摄氧量和心率的影响,发现不同海拔递增负荷下机体运动的特点。方法以78名在岗工人为测试对象,采用功率车模拟劳动负荷,使用心肺功能测试系统收集不同海拔和不同劳动负荷下的肺通气量、心率、摄氧量。结果不同海拔递增负荷下的摄氧量随着负荷的增加而增加,但与海拔无关(F=0.508,P>0.05)。肺通气量随劳动负荷和海拔增高而增加,但折算成标准状态下的肺通气量后,同样显示不同海拔处同等负荷下肺通气量无显著性差异(F=1.131,P=0.344)。心率随着劳动负荷的增加而增加;高原的静息心率较平原高。结论摄氧量与劳动负荷有密切关系,而与海拔无关,可作为高原环境下劳动强度评价的可靠指标。2 500 m以上各个海拔的心率值较接近,提示2 500 m可作为人体适应的海拔分界值。

Objective To explore altitude and physical workload combination effect on oxygen uptake and heart rate,and characteristics in different increasing altitudes and physical workloads.Methods Seventy eight healthy males were recruited.At different altitudes,an incremental cycle ergometer tests until volitional fatigue were performed on all participants.Physiologic parameters,including Oxygen uptake(VO2),Minute ventilation(VE),and Heart rate(HR) were recorded in test system which was connected with computer.Results VO2 increased with the increasing intensities of physical workloads instead of elevations(F = 0.508,P >0.05).VE were affected by intensities and altitudes.However,VE in standard temperature and pressure,dry(STPD) were steady at a specified intensity,which did not rely on the elevations(F = 1.131,P = 0.344).HR enhanced parallel as the workload increased,and HR was higher in plateau than in plain.Conclusion VO2 in healthy males depended on exercise intensity and was independent of elevation.Therefore can be used as a reliable indicator to assess physical workload in plateau.HR was steady at altitudes over 2500 m,which suggested that 2500 m can be a cut-off point in physiologic response of high altitude.