Group fitness programs represent modern forms of organized exercise under the guidance of professionally trained trainers. The basic division of group fitness programs includes four categories: cardio programs aimed at developing and preserving cardiorespiratory health, muscle programs aimed at shaping and strengthening muscles, cardio-muscle programs that combine both aspects, and body and mind programs aimed at developing physical and mental balance. The key role of trainers in group fitness programs is the creation of a motivating atmosphere, proper training preparation, high-quality demonstration of exercises and the ability to motivate exercisers. The primary goal of this research is to determine the factors that influence the choice and retention of group fitness programs in the surveyed population, and the secondary goal is to analyze the differences between respondents who regularly attend group programs and those who do not, and the differences between male and female respondents. Based on the set goals, four hypotheses were defined which state that there is a statistically significant difference in the importance of the quality of training and the arrangement of the training space between men and women, between age groups, between respondents who have experience with group training and those who do not, and between respondents who are currently participating in group trainings and those who do not. Through the implementation and analysis of this research, it has been proven that participants single out hygiene in the exercise area, correcting the exerciser by the trainer, the atmosphere at the training session, i.e. the relationship with others and the expertise of the trainer, as the most important items when choosing and staying on group fitness programs. Also, factors related to the quality of training largely depend on which group of exercisers it is about, where women, older people, people with experience and people who actively attend group training for a longer period of time emphasize greater importance in the quality of training.