海拔3417m地区藏汉少年运动负荷下心肺功能的变化

CHARACTERISTICE OF CARDIO-PUIMONARY FUNCTIONS DULING EXERCISE IN SCHOOL CHILDREN AT HIGH AL TITUDE

用逐级负荷踏车试验和心阻抗图同步测定了海拔3417m地区29例世居藏族和36例移居汉族少年(年龄13～16岁)运动前后的心肺功能。结果发现,两组运动前心肺功能的各参数均无明显差异。而最大运动后,藏族的每分通气量,氧耗量,心翰出量和每搏量显著大于汉族,(P<0.05～0.01).最大耗氧量和最大心输出量之间呈直线相关(r=0.414,P<0.05)。运动前的SaO_2无差异,运动负荷后两组SaO_2均明显下降,但汉族少年下降的幅度更显著,且恢复缓慢。最大运动功率藏族组大于汉族(P<0.05)。上述表现说明,高原藏汉人群心肺功能的差异可能始于少年时期,其原因似于生长发育期的环境和/或种族遗传有关。

Cardio-pulmonsry functions before and after exercise were measured by the Jeager cycle ergomter and the Nikonkonoe(impednace cardiogram) in 29 Tibetans and 36 Hans school childern(aged 13～16yr) at altitude of 3 417m above sea level. The results showed that the psremeters of cardio-pulmonary function in both groups were not different at rest,but at maximal effort,the Tibetan compariled to Han had higher minute ventilation (P<0.05),oxygen uptake (P<0.05),stroke volume (P<0.05) and cardic-output(P<0.01). There was linear correlation between vo_2max and COmax(r=0.0414, P<0.05). The averge arterial oxygen saturations of Tibetan and Han were 89.17±0.91% and 88.15%4±0.81%(mean±SD) respectinely, (P>0.05) at rest ;and at maximal exercise they were 83. 66±0.76% and 79.36%±1.17%(P<0.05), respectively,and period of recovery was very slow in Han. The maximum work load in Tibetan and Han were 127.57±4.14W and 117.26±4.76W, respectively(P<0.01). The results showed that the difference between Tibetan and Hart may begin frome juvenile period, the causes of which may be due to the enviroment of growth and development as well as genetic factors.