Background and Aims: Examining the differences between sea-level training programs and altitude offers important new perspectives on how environmental influences affect physiological adaptations and athletic performance. By being aware of these variations, coaches and athletes can tailor training plans to the unique conditions of altitude, which may improve performance in terms of endurance, oxygen use, and general athletic ability. Thus, this study aimed to investigate the effects of altitude training on physiological adaptation and performance in Chinese elite male marathon runners compared to plains training. By comparing the results of altitude training with those of sea-level training, this study sought to determine whether altitude training has a significant advantage in terms of physiological adaptation and performance enhancement for the Chinese elite male marathoner. In addition, exploring the variability of altitude training responses will help to inform an in-depth understanding of training strategies affecting elite marathoners and help to optimize performance enhancement methods in endurance sports. Methodology: Thirty-two Chinese elite male marathon runners will be recruited and subjected to a randomized controlled trial (RCT) in which they will be assigned to either a high altitude or plains training group. SPSS was used to perform independent samples t-tests and paired samples t-tests on the data of technical indicators. Both groups will receive structured and standardized training for a predetermined period, with the altitude of the high-altitude training set at 2366 m for 8 weeks. Results: (1) In the experimental group, the differences in red blood cells (RBC), maximal heart rate (HRmax), maximal oxygen uptake (VO2max), and full marathon performance before the altitude experiment compared to after the altitude experiment were significant (P=0.001); the differences in maximal anaerobic power and hemoglobin (HB) before the experiment were substantial (P<0.005); and the differences in maximal heart rate (HRmax) between the 28 days of the experiment and the post-experiment were substantial. (HRmax) difference was substantial (P=0.001). (2) The red blood cells (RBC), hemoglobin (HB), and maximal oxygen uptake (VO2max) of the experimental group were significantly higher than those of the control group compared with the control group (P < 0.005) Conclusion: The results of the study showed that eight weeks of altitude training at an altitude of 2,366 meters above sea level could improve the athletes' performance in the marathon and aerobic capacity, and could be used in the training of marathon runners.