Abstract: Objective: To improve the native plateau youth endurance athletes' aerobic ability through the intervention of sub-platitude training, and compensate the intensity lost in plateau training on the basis of optimizing the function of heart and lung and the use of oxygen in muscle tissues, aiming to exert a more positive and far-reaching influence on the development of the endurance sports in China through reasonable sub-plateau training intervention. Methods: 48 youth native endurance athletes from Ganzi Prefecture of Sichuan Province were divided into experimental group A ( 3 weeks on plateau- 2 weeks on sub-plateau-1 week on plain) and control group B (5 weeks on plateau-1 week on plain) to participate in the experiment. Results: (1) compared with group B, group A presented better performance in limit running, used shorter average time in 400 meters running, much closer to their shortest time in 400 meters running. Both their average longest time and shortest time in 400 meters running were shortened, and there were significant differences in some indicators between the two groups (P<0.05). (2) Compared with group B, the maximal oxygen uptake, heart rate, blood oxygen saturation, blood lactic acid, blood glucose and other indicators of group A showed a tendency to stronger aerobic working ability, and there were significant differences in some indicators (P<0.05). Conclusion: After 2 weeks of sub-plateau intervention training, the young native plateau athletes have been able to give full play to their existing physiological advantages. Compared with the mere plateau training, the sub-plateau intervention training consolidated and improved the athletes' aerobic exercise ability in a better way, and made their physiological function and athletic performance combined effectively. This helped make athletes fully prepared for participating in matches on plains.

Key words: altitude training, sub-Plateau, intervene, native plateau athletes, endurance