Background: Sport provides many benefits for the human body. The level of health and fitness of people who regularly exercise is better than those who rarely exercise. These benefits are obtained by performing the correct procedures and avoiding adverse risks. Air pollution is one of the adverse risks in sports, especially those carried out outdoors. Air pollution in industrial areas such as the capital city of Karawang Regency, West Java, Indonesia is worse and needs attention. The purpose of this study was to determine differences in aerobic endurance in two air polluted environmental conditions, especially fine particles with a diameter of less than 2.5 Micrometre (PM2.5). Methods: This study used a crossover design for two periods. The research location consists of two different places in Karawang Regency, West Java, namely Singaperbangsa Stadium with high PM2.5 and Cinta Lake with low PM2.5. The research subjects were 22 undergraduate students with healthy status who were selected using purposive sampling. The VO2max value was obtained by the Cooper Test method. Each study period, subjects did 15 minutes of running exercise with submaximal intensity (80-85% maximal heart rate) for 5 consecutive days. The washout period was carried out for 10 days. Aerobic endurance based on maximal oxygen consumption (VO2max) was measured before and after in both study periods. Results: Both research points have the same climate but significantly different PM2.5 concentrations. Exercising regularly at the two study sites increased aerobic endurance. Exercising in an environment with a low PM2.5 concentration had a higher increase in VO2max and was significantly different from exercising in a location with a high PM2.5. Conclusion: Regular exercise can increase aerobic endurance, but if done in an environment with a high PM2.5 concentration, it will inhibit the increase in VO2max compared to an environment with a lower PM2.5 concentration.

Keywords: exercise, aerobic endurance, air pollution, PM2.5