The main purpose of this study was to assess the effects of aerobic training to the performance ofrnmiddle and long distance athlete. It was evaluated the training plan, examined the performance ofrnthe athlete, the improvement rate, and the gender difference of an athlete with the use ofrnperformance predictive (Balke) test, document analysis and observation check list techniques.rnThe research was used comparative study method with the purposive sampling technique,rninvolved 10 male and 6 female athletes which were selected from middle and long distancernevents. The data gathered from this technique were analyzed and interpreted with percentage andrnSPSS one way ANOVA statistic method. The results of the findings it shows that the trainingrnplan was followed the principles indicated to the literature except the difference with increasedrnvolume. The findings also shows the performance predictive test result of group multiplerncomparisons indicated that there was a significant difference between test one vs. two, one vs.rnthree and one vs. four and there was no a significant difference between test two vs. three, two vs.rnfour and three vs. four. The results of male comparison indicated that there was a significantrndifference between test one vs. three, one vs. four, two vs. three, and two vs. four, but there wasrnno significant difference observed between test one vs. two and three vs. four. The results of malerncomparison indicated that there was a significant difference between test one vs. two, one vs.rnthree and one vs. four, but no significant difference observed between test two vs. three, two vs.rnfour and three vs. four. Depending on their VO2max level male has been showed averagernimprovement of 0.91% and average mean improvement rate of female was 1.84%. Finally thernresearch showed that there was a difference in level of VO2max between male and female athlete.rnKey terms: aerobic performance, maximum oxygen uptake (VO2max), performance predictiverntest (Balke test), aerobic training, altitude.