逐级增加等长运动负荷对女运动员心功参数的影响

EFFECTS OF GRADED ISOMETRIC EXERCISE ON CARDIAC FUNCTIONAL PARAMETERS IN SPORTSWOMEN

用阻抗法测定了17名省级女运动员和20名青年女学生静态、20%、40%、60%和80%单手最大握力(MVC)状态下的心率(HR)、动脉血压(BP)、收缩间期(STI)和每搏输出量(SV)等。静态下,运动员组心率较缓(p<0.01)、收缩压和舒张压较高(p<0.01,p<0.05)。电机械延迟时间(QS_1)和校正的左室射血时间(LVET_c)较短(p<0.05,p<0.01)。等长运动时, 两纽都表现为心率增速、血压升高、LVET_c延长;60%和80%MVC时QS_2、LVET、QS_1缩短;80%MVC时SV减少。但运动员组的心率增速、LVET_c延长和SV减少的程度都明显低于学生组,有显著统计学差异。PEP/LVET、IVCT、CO的变化无统计学意义。本文观察到:青年女学生及运动员在逐级等长运动时的心血管反应;在80%MVC时运动员组的心率储备和心力储备较学生组明显为大。

Systolic time interval (STI), heart rate (HR), blood pressure (BP) and stroke volume (SV) were measured by impedance cardiography at 20%, 40%, 60% and 80% maximal voluntary contraction (MVC) in 17 sportswomen and 20 girl students. At rest the HR was lower (p<0.01), systolic blood pressure and diastolic blood pressure were higher (p<0.01, p<0.05), QS_1 and left ventricular ejection time corrected for rate (LVETc) were shorter (p<0.05, p<0.01) in sportswomen as compared with the values in girl students. During isometric exercises, the mean values of HR, B P and LVETc increased, the mean values of QS_2, LVET and QS_1 at 60% and 80% MVC decreased, SV at 80% MVC decreased both in sportswomen and in girl students, However, the degrees of increase in HR and LVETc and decrease in SV in the sportswomen were not as great as in the girl students. Changes of PEP/ LVET, IVCT and CO during isometric exercise had no statistical significance. This study showed that during graded isometric exercise the reserves of HR and cardiac contractility at 80% MVC in sportswomen were better than those in girl students.