## 4 Discussion
Low correlation coefficients of angular velocities may also suggest a different performance style or a different model for transitioning from Phase 1 to Phase 2 of the performance technique. This indicates that these four gymnasts follow a different model (or style) of movement when entering the second phase of the CHCH performance technique. Based on the different angles observed in the first phase of the CHCH performance technique, it can be concluded that there are three distinct ways in which the finalists on the uneven bars initiate the CHCH (Figure 7):  
1. The technique is performed with a stretched body and a slightly pronounced flexion in the hip joint throughout the entire execution of Phase 1, as shown in Stick Figure 1 (four female competitors: [PERSON], [PERSON], [PERSON], and [PERSON]). In the first part of the movement, the body is almost fully extended in the hip joints (the angular velocity is close to zero, with the angle values averaging slightly below 180 degrees). 2. With a stretched body, but at the moment when the shoulders begin the backward movement, a short and quick extension is noted in the hip joint, the so-called \"Courbet\"(this refers to an extension in the hip joint with peripheral support, where the legs appear to stand while the hips drop down, as shown in Stick Figure 2. This movement is observed in six competitors: [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], and [PERSON]). 3. Hyperextension in the hip joint as shown in Stick Figure 3 is determined in three competitors ([PERSON], [PERSON], and [PERSON]). Generally, the results revealed high correlations across kinematic variables, with most correlations ranging from 0.81 to 1.00, indicating consistent execution patterns among gymnasts. Variations in angular and angular velocity parameters, especially for the hips and shoulders, indicate the presence of different technical approaches. However, these variations do not seem to impact overall performance success. Despite individual stylistic differences, elite gymnasts maintain a high level of technical consistency in performing the CHCH. Techniques can be categorized into different styles, general or specific, influencing the selection process. Technique selection is driven by skill requirements and the performer's physical characteristics [26]. Each gymnast incorporates personal style into their performance, deviating to varying extents from the ideal model. A gymnast's specific style depends on factors such as anthropometric characteristics and velocity/muscular properties. A gymnast's unique style is a defining aspect of their overall gymnastics' skill. Motor control and synchronization are crucial for learning gymnastics skills [27], where practice is the most important factor in skill effectiveness [28]. However, a biomechanical analysis of movement must be complemented with muscle activation analysis at each stage of the CHCH, to avoid forming incorrect movement technique patterns during the training process when learning a new exercise. Once adopted, motor performance can evolve into an individual style, while the ideal model for performing gymnastics skills remains consistent. Our kinematic analysis of movement technique leads to an optimized training process, allowing for skill mastery in a shorter period of time. Successfully mastering the technique means that the motor action becomes automatized as stated in [29], reducing the need for excess energy expenditure during the movement. Hence, top-level gymnasts must have exceptional physical and technical preparation, which varies according to their individual characteristics. Flexibility and strength are two critical abilities that cannot be neglected in the training process [30], and for elite gymnasts, they must be trained at maximum intensity. Regarding anthropometric characteristics, a gymnast's height and weight significantly affect the learning of new skills on the uneven bars [31]. The CHCH, a rotational-type skill, is influenced by height and body mass, which affect the rotational speed of the movement.