1.    Introduction
Maintaining a healthy lifestyle is imperative and essential across all age groups (1, 2). People engage in sports programs for various reasons. Interest and participation in artistic sports and martial arts such as Karate, Taekwondo, Kung Fu, and Wushu have significantly increased in recent years. For instance, Birrer (1996) reported that more than 75 million teenagers worldwide are actively involved in at least one combat sport (2). One of the requirements for scoring points in these martial arts involves physical contact between the athlete's body and their opponent's, such as kicking the opponent's body (6, 7). In these sports, the incidence of both minor and severe injuries among athletes is high, emphasizing the necessity of investigating proper technique acquisition from a mechanical standpoint (8, 9). Thus, identifying the factors affecting skill development is crucial for coaches and sports science specialists. Sports biomechanics can significantly enhance athletes' peak performance through movement analysis, and discerning differences in foot kicks among skilled athletes can greatly aid coaches and novice athletes in improving performance and preventing injuries. In this context, one of the most effective methods for measuring the movements of combat sports is using motion analysis devices. Therefore, based on the aforementioned rationale, the aim of this study is to examine differences in the execution of combat kicking techniques among skilled practitioners of Karate, Taekwondo, and Wushu.
2.    Methods
The study involved 12 athletes in two disciplines, Taekwondo and Wushu, divided into groups of six participants at an expert level for each discipline and aged above 18 years. The sampling method employed in this research is accessible and practical for the intended purpose. Following the division of subjects into two groups based on their respective sports disciplines, they underwent three main rounds of kicks against a manikin, with a 30-second interval between each round. After each kick, participants provided feedback on their performance, and the best kick according to each participant was recorded after three attempts. To analyze and record the kicks, the laboratory utilized eight motion analysis cameras, calibrated to zero error before capturing the kicks. Following environment calibration, markers were affixed to the subjects' bodies, and all kicking movements were recorded by attaching a light marker to each participant's body. The motion analyzer device was used as the primary tool in this study, exhibiting acceptable validity, stability, and suitability for movement analysis. After data collection via cameras, the best kick from each participant was subjected to analysis, and paired t-tests were conducted to compare kinematic variables between Taekwondo and Wushu athletes. Statistical analysis was performed using SPSS version 21 software with a significance level set at 0.05 (10).
3.    Results
Table 1 presents a paired t comparison of the maximum rotational kicking speed of skilled Taekwondo and Wushu (Sanda) athletes. The results of the paired t-test for the maximum rotational kicking speed of skilled Taekwondo and Wushu (Sanda) athletes showed that there was no significant difference in the variables of kick duration, maximum foot speed until the moment of impact, foot speed at the moment of impact, and knee angle at the moment of impact between Wushu (Sanda) and Taekwondo. However, significant differences were found in the variables of maximum knee angle in the flexion, hip flexion angle at the moment of impact, lateral angle (y and z) of the thigh at the moment of impact, amount of internal rotation of the pelvis (in terms of angle), amount of lateral rotation of the pelvis, maximum amount of internal angular changes of the thigh over time, and maximum amount of lateral angular changes of the pelvis over time.

4.    Conclusion
The primary reason for the difference in kicks between Wushu and Taekwondo players stems from the specific type of kick required in each discipline. For instance, the higher speed of kicks in Taekwondo leads to a shorter duration of the kick (back and forth leg) among Taekwondo players (11). Additionally, Taekwondo athletes exhibit higher foot speeds up to the moment of collision compared to Wushu athletes (11). Concerning the lateral angle (z and y) of the thigh at the moment of impact, Wushu athletes tend to hit with greater force to score points, resulting in a smaller angle at the moment of impact and increased leg pressure for a stronger impact (12). Regarding the internal and external rotation of the pelvis (in terms of angle), Wushu athletes demonstrate higher levels of internal rotation due to the requirement for greater impact power (13). Conversely, Taekwondo athletes, not needing to hit as forcefully, exhibit less internal rotation and more external rotation (19). In terms of the maximum amount of internal thigh and lateral hip angular changes over time, the intensity of blows in Wushu compared to Taekwondo, and the higher speed of blows in Taekwondo compared to Wushu, are justified (14). Furthermore, concerning the maximum knee angle in the vertical axis, Wushu athletes typically need to bend their legs more for a stronger impact. As for the knee angle at the moment of impact, which was not significant in this study, it appears that both Taekwondo and Wushu athletes attempt to bend their legs fully at the moment of impact. However, regarding the hip flexion angle at the moment of impact, the potential difference may be attributed to the tendency of Taekwondo players to target higher on the opponent's body (for more points), compared to the lack of emphasis on leg kicks in Taekwondo compared to Wushu (17, 18).
Ethical Considerations
Compliance with ethical guidelines
There were no ethical considerations to be addressed in this research.
Funding
This research did not receive any grants from funding agencies in the public, commercial, or non-profit sectors.
Authors' contributions
All authors contributed equally to preparing the article.
Conflicts of interest
The authors declared no conflict of interest.