Study On The Effect Of Altitude Training On HIF-2α And Lung Function In Tibetan-Chinese Middle Distance Runners

Objective:To investigate the possible effects of plateau training on lung function and EPAS1/HIF-2αin Tibetan athletes living on the plateau and Han athletes living on the plain,and to examine whether the lung function parameters of Tibetan and Han athletes are related to hypoxia-inducible factors.The study was conducted to investigate the possible effects of plateau training on lung function and EPAS1/HIF-2αin Tibetan and Chinese athletes,and whether there was an intrinsic association between lung function parameters and hypoxia-induced factors.Research methods:The study was conducted by literature,bibliometric method,expert interview method,and experimental method,and this time the experimental method was mainly used.（1）Subjects:The subjects were Tibetan athletes living in the plateau and Han athletes living in the plains,and the subjects were all athletes with≥4years of training and competition experience in the 800-5000m endurance event.The plateau Tibetan athletes are the middle and long-distance runners of Qinghai provincial team,including 2 healthy athletes,5 first-class athletes and 9 high-level athletes who have not yet reached the level,because one player withdrew from the test due to injury or illness,so a total of 15 athletes were included in the plateau test;the plain Han athletes are the middle and long-distance runners of Liaoning provincial team,including 2 national healthy athletes,6 first-class athletes and 6 high-level athletes who have not yet reached the level,so a total of 14 athletes were included in the plain test.14 athletes were included in this test;they were grouped according to their place of residence and defined as plateau group and plain group（there was no statistical difference between the two groups in height,weight,age and other basic indexes）.（2）Test indexes:respiratory muscle strength,forceful lung volume（FVC）,volume in one second（FEV₁）,maximum ventilation volume（MVV）;small airway flow rate,maximum expiratory flow rate（PEF）;lung volume,lung volume（VC）,compensatory expiratory volume（ERV）,tidal volume（VT）;hematology,hemoglobin（HGB）,erythrocyte pressure product（HCT）,blood oxygen saturation（SaO₂）.Genomics,hypoxia-inducible factor（EPAS1/HIF-2α）.The correlation test showed that the EPAS₁/HIF-2 expression of Han athletes was correlated with VC and SaO₂,and there was a linear relationship.Research resultsThe lung volume parameters VT increased by 34.62%,VC increased by 20.5%and ERV decreased by 12.5%;pulmonary ventilation parameters VE increased by 50.03%;small airway flow rate parameters PEF increased by 17.40%;respiratory muscle strength parameters FVC increased by 24.49%,FEV1 increased by 14.65%and MVV increased by 26.16%in Han athletes who lived in the plains for 6 weeks of plateau hypoxia training.MVV increased by 26.16%.（2）The 6-week plateau hypoxia training did not fluctuate the lung volume parameter VT but its basal and post-training values were higher than those of the Han athletes;the lung ventilation parameters of the Han athletes changed significantly,VC increased by 8.72%,ERV increased by15.46%;the lung ventilation parameter VE increased by 32.73%;the small airway flow velocity parameter PEF did not change,and FEV1 increased by 6.40%.FEV1increased by 6.40%;respiratory muscle strength parameters FVC increased by25.47%,FEV1 increased by 6.40%,and MVV increased by 13.91%.（3）The HGB,HCT,and SaO2 of the Tibetan athletes living on the plateau and the Han athletes living on the plateau were maintained near the baseline values without significant changes,indicating that they were well adapted to the hypoxic environment.Hypoxia"induced a"stress-stimulus-decline-stabilization"of EPAS1/HIF-2αin Han athletes adapting to the hypoxic environment,while Tibetan athletes showed a"stress-stimulus-decline-stabilization"of EPAS1/HIF-2α.In Tibetan athletes,it was"Stimulus-Rising-Stable".Research conclusions（1）Six weeks of plateau training enhanced pulmonary ventilation and improved performance in Tibetan athletes living on the plateau and Han athletes living on the plain,with Han athletes gaining more significantly.（2）The hypoxic environment induced stress in the hypoxia-inducible factors of the Han athletes to enhance the adaptation ability to the hypoxic environment.（3）The hypoxia-induced factor and pulmonary ventilation indexes are few and not high confidence evidence,so it is not recommended to be used as a plateau training assessment index.