In this master's thesis, the goal is to explain the importance of endurance for performing tasks within the scope of work of the Police Intervention Unit. The Police Intervention Unit, as a component of the Directorate of Police of the Ministry of the Interior of the Republic of Croatia, is undoubtedly one of the most utilized components for performing a wide range of tasks prescribed by the Law on Police Duties and Authorities in today's age. The employees of the Police Intervention Unit are engaged daily in executing the most complex and challenging tasks within the areas of their Police Deparmtments, but also throught the entire territory of the Republic of Croatia, where they operate collectively. The police intervention unit employee, due to the job description, falls into special populations. Today, we can also refer to them as tactiacal athletes because training is part of their daily routine alongside their offical duties. In order to be successful in executing their basic daily or special tasks, an intervention police officer must have well-developed functional abilities. First and foremost, they need a solid foundation of well-developed aerobic capacity, foolowed by equal well-developed anaerobic capacity. The main role in this lies with the program leader of specialized training in the unit, whose task is to implement the general and specialized physical preparation programs. To effectively design and conduct training for police officers, the program leader of specialized traing must be well-educated, keep up with the latest developments, and utilize modern endurance training methods appropriate for special populations. Special populations traning differs significantly from training of professional athletes, both in terms of requirements, training conditions, and lifestyle. A high level of the aforementioned abilities can be achieved and maintained only through systematic fitness training, highlighting the significance of overall fitness preparation. The training process for intervention police officers is carried oud through the most modern methodological forms, which involve the application of specific (not just any) kinesiological stimuli, elements of police, and integrated training.