## 1 Introduction
For static and dynamic balancing tests, performed before and after a dance session (Hungarian folk dancers), via examination with eyes closed and open, greater deviations of the joints are found on the non-dominant leg, and oscillations in the posterior direction are significantly higher after dancing [32]. The increased intensity of physical activities generates a reduction in the values of static balance after effort (One leg standing test), but a break of 15 min will generate an increase in the values for this test [33]. The need for individualized exercise programs for obese children, aimed at increasing mobility and stability of the ankle, improving postural balance, stimulating the proprioceptive system and strengthening the lower limb muscle groups are stipulated by [34]. They recommend static and dynamic exercises, with eyes closed and open, performed on various surfaces (stable and unstable). The idea of the efficiency of unstable surfaces is also supported by [35]. A comparative study of volleyball players (elite level, x = 23.6 years) shows that the application of classic balance training for 12 weeks is more effective than the variant of sand training, which leads to worsening of static balance (evaluated using the Romberg test), in the opinion of [36]. Applying yoga exercises/asanas to obese young people (21-25 years old) produced significant improvements for the static and dynamic balance evaluated using one leg standing balance and a functional reach test [37]. A similar study at the level of students (18-25 years old) confirms the effectiveness of yoga asanas for the performance of static balance (stork test) and muscle strength, according to [38]. Applying balance training for obese people (20-50 years old) for 4 weeks improved their static and dynamic performance [39]. Implementing a dynamic core exercise (DCE) program in the warm-up part of physical education lessons for 6 weeks for 10-11 year olds has beneficial and significant effects on physical parameters., flexibility and balance, according to [40]. A solution to improve the balance for those sitting on a chair/sitting postural balance for about 10 h a day is based on the use of a linear actuator and MR damper. The device offers combined exercises to strengthen the muscles of the back that are too weak and to relax the contracted one, regulating the muscular activity of the trunk between the dominant and the non-dominant part [41]. Applying an artistic gymnastics program (12 weeks \(\times\) 2 workouts/week \(\times\) 60 min/sess) generated improvements in results related to static balance (flamingo test), strength and flexibility for students in physical education and sports in Turkey [42]. A 6-weekprogram based on Wii Fit exergames had positive effects on static balance and motor competence for young normal weight and obese college students [43]. _The purpose of the study_ is to investigate the way in which the gender and the classification of students in different BMI levels influence the applied performances in static and dynamic balance tests, with identification of the registered differences and comparison of the results obtained in other scientific studies. _Working hypotheses_:  
**H1. **_We estimate that the independent gender variable will generate significant differences in the registered dependent variables (values obtained from the applied equilibrium tests)._  
**H2. **_We estimate that the independent variable BMI steps (with the underweight, normal weight and overweight steps) will generate significant differences between the performances obtained, for the entire set of tests used in the assessment of balance._  
**H3. **_We assume that we will obtain strong and significant correlations between BMI values and performance on balance tests, in the sense that poor performance on tests will be associated with an increase in the BMI._