Introduction: Taekwondo athletes’ performance is affected by their level of physical fitness. High-level athletes must have good physical fitness to perform difficult techniques and complex sets of movements with high specificity. Objective: Verify the influence of high-intensity training on fitness levels for the selection and daily training of taekwondo athletes in colleges and universities. Methods: In this study, 47 high-level taekwondo athletes from the Capital Institute of Physical Education were considered and statistically analyzed employing literature, expert interview, tests, mathematical statistics, and logical analysis. The factors influencing physical fitness were determined. Results: Five first-level, nine second-level, and 15 third-level test indicators based on the combination of general fitness and specific fitness of athletes were determined. Fitness test analysis was performed before and after 12 weeks of daily high-intensity training demonstrating that the athletes’ physical quality showed an upward trend, especially in terms of strength, endurance, and flexibility. Still, speed and agility showed no statistical change. Conclusion: Fitness training of high-level taekwondo athletes should be combined with particular techniques, focusing on training the five qualities of strength, speed, endurance, agility, and flexibility. It is recommended to individually plan the training cycle and intensity of each training session, to carry out a targeted training plan, and to ensure a training plan with regularity. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.