Background: Physical fitness training is very important for sports performance. The objective is to assess the different capacities of athletes like speed, strength, flexibility, leg muscle power, and VO 2 max. The purpose of this study was: (1) to determine the current status of physical fitness of Yogyakarta athletes, (2) to compare the physical fitness performance on the standard's physical fitness value, (3) to show the effects of physical fitness on the athlete's performance. Research methodology: this is exploring research with a mixed-method qualitative and quantitative study. The sample of this study was 39 subjects from Yogyakarta. The subjects were taken randomly. The subjects were aged between 13-18 years, and they were from many various parties of Yogyakarta. The content of the training was squat jumps: 10 to 15 repetitions, standard push-ups: 10 to 15 repetitions, calf raises 15 to 20 repetitions, bench dips: 10 to 15 repetitions, abdominal crunches: 15 to 20 repetitions, jump rope: 60 seconds, plyometric exercise, sit-ups, press-ups, squats, lunges, and step-ups within three times per week for six weeks. The facts series technique was a physical battery test on the playground. Data were analyzed with descriptive statistics. The result showed that Yogyakarta athletes still have low physical fitness with a P-value of 0.000. Conclusion: Yogyakarta athletes still hold low physical fitness like speed, VO 2 Max, flexibility, explosive strength, power, and coordination.