Tehran University of Medical Sciences Iranian Journal of Public Health 2251-6085 51 10 2022 10 04 2253 2261 Lili Guo Public Teaching Department, Pingdingshan University, Pingdingshan, 467000, China 2022 07 30 2022 09 02 Background: The study aimed to discuss the influences of 24-form Tai Chi on cardio-pulmonary functions, exercise performances, and cognitive functions of the aged. Methods: Forty old people in Pingdingshan of China were selected through convenient sampling method from 2020 to 2021. They were randomly divided into the observation group (n=20) and the control group (n=20). The observation group exercised 24-form Tai Chi for 8 weeks, three times per week, 45 min per session. The respondents were evaluated by cardiopulmonary exercise testing, sitting-standing test, 6-min walking test, and the Berg balance scale. The P300 test was performed to evaluate the cognitive functions of respondents. Results: After the intervention, the observation group was significantly (P<0.05) superior to the control group concerning maximal oxygen consumption, anaerobic threshold, vital capacity, stroke volume (SV), cardiac output (CO), left ventricular end-diastolic diameter (LVEDD), left end-diastolic velocity (EDV), sitting-standing test, 6-min walking test, and the Breg balance function scores, showing statistically significant differences (P<0.05). The content of body fat and body mass index (BMI) of the observation group decreased significantly, whereas muscle mass and fat-free mass increased dramatically, which were however significantly lower than those of the controlled group (P<0.05). Moreover, the P3b amplitude of the observation group increased significantly (P<0.05) and was significantly higher than that of the control group (P<0.05). Conclusion: The 24-form Tai Chi not only improves cardio-pulmonary functions and exercise performances of the aged but also increases cognitive functions of the aged. https://ijph.tums.ac.ir/index.php/ijph/article/view/29439 https://ijph.tums.ac.ir/index.php/ijph/article/download/29439/7742