复合营养素制剂对高原青年营养状况与耐低氧能力的干预作用

目的：观察复合营养素干预对机体营养状况与低氧耐力的影响。方法：选择进驻海拔3700m半年以上的健康男性青年40名,随机分成2组（n=20）：对照组和干预组。膳食调查采用称重法。对照组和干预组分别服用炒面制剂和高原维康制剂20d后,急进5100m高原。实验前、后分别测量心率（HR）和血氧饱和度（SaO2）;同时采血测定血中一些维生素和矿物质浓度。结果：膳食调查结果表明三大产能营养素供能比例不够均衡;矿物元素中Ca摄入不足,维生素中VA、VB2摄入量均未达到推荐摄入量（RNI）要求。血清测定结果表明干预前受试者矿物元素Ca、Mg和VA浓度低于正常参考值,V殴浓度也在正常范围的较低水平。高原维康制剂干预后,血清Ca、Mg、Zn浓度和VA、VB2水平显著升高或接近正常,说明营养状况得到改善。由3700m进入5100m后,干预组与对照组比较HR升高幅度明显减慢,SaO2的下降幅度显著减少。结论：复合营养素制剂能明显改善机体的营养状况以及对低氧环境的适应能力。

Intervention of nutritional status and hypoxia endurance by a nutritional supplement in young adults living at high altitude

Aim: To investigate the effects of a nutritional supplement on nutritional status and hypoxia endurance in young adults living at high altitude. Methods: Forty healthy male young adults were recruited and randomly assigned to control and intervention groups. The nutrition survey was carried out using weighing method. The intervention group was given a nutritional supplement specifically designed for use at high altitude, while the control group was treated with a supplement made of stir-fried flour. After 20 days of supplementation, they marched from the altitude of 3 700 m to 5 100 m. The changes in HR, SaO2, serum concentrations of VA and VB2 and some minerals were measured. Results: The results of nutrition survey showed that the ratio of three macronutrients was not adequate and the intakes of calcium, VA and VB2 were below Chinese RNI.The serum concentrations of calcium, magnesium and VA were below normal references. The serum VB2 concentration was at the low level of normal reference. The nutritional supplement could increase the serum concentrations of calcium, magnesium, VA and VB2, indicating an improved nutritional status. The changes in HR and SaO2 were diminished in intervention group compared with control group. Conclusion: The nutritional supplement can improve nutritional status and increase the hypoxia endurance in young adults living at high altitude.