## 1 Introduction
Several phases are recognized in punch execution, as well as different speeds of contralateral upper limbs during performance [21]. It has been documented that kinematic and neuromuscular activity in the punch occurs within 400 ms, with a proximal to distal sequence of activation [22]. The peak of the wrist linear velocity reaches up to 7.3 \(\pm\) 0.8 m/s in elite athletes [23]. It is found that athletes' competing experience makes a difference in perceptual and reaction skills, neuromuscular control indicators, and performance. The elite karate athletes react and accelerate the wrist more quickly than sub-elites. In addition, they are able to brake more quickly, which makes the technique less obvious to the opponent [24]. [PERSON] [25] found that in the first phase of the movement lasting 160 ms, hand speed increases continuously from 0 to 12.5 m/s. The average acceleration obtained in this research was about 78 m/s\({}^{2}\). Considering the contribution of the lower part of the body in the punch execution [19], this should also be taken into account. That is, through rotation of the pelvis, or the body, the joint sequence of the lower limb is linked to the joint sequence of the arm [26]. It is found that a greater shoulder extension is a characteristic of karate fighters. They are also able to generate high values of preferred velocity to perform joint movements [27]. Studies revealed that different task orientations and conditions of execution influence punch kinematics. For example, acceleration values differ depending on the primary orientation towards force or speed at a fixed or self-selected distance [1]. Moreover, changing distance length has a significant influence on force production and punch acceleration [28]. For these reasons, the analysis of RP should be founded on the conditions that replicate training and combat environments. Contrary to that, a laboratory approach is dominant. Lately, researchers have offered various systems tending to improve combat sports training. They rely on technological advances (computer vision pose estimation, vision and inertial sensing system, sensors, and convolution neural networks, novel non-conventional system), aiming to understand punch execution and develop efficient tools for monitoring and enhancing combat technique in different aspects [21; 29; 30; 31]. However, joint kinematics is traditionally restricted to laboratory research [3; 4]. A frequently employed method in the biomechanical analysis of punching techniques in studies, in addition to the force platform [20; 32] and electromyography [22; 33], is motion capture carried out with marker-based optical technology (sometimes combined with force platforms) [20; 23; 34; 35; 36; 37; 38; 39; 40]. Unlike other proposed systems, force platforms are not able to provide information about the movement prior to contact, which disables insight into the developmental phase of the punch. EMG overcomes this problem, but its main disadvantage is that the apparatus is attached to the body, which limits the athlete's movements. Apart from that, performing punches in dynamic conditions is a special challenge because of the complexity of movement in real settings and possible noise due to speed or muscle size. Physiological processes that are more pronounced or only occur under conditions of high exertion might also affect the shape or size of the corresponding EMG signal. In addition, electromyograms must be normalized in order to facilitate interpretation, offer adequate reliability, and provide a representative measure of muscle activity [41]. The marker-based optical systems are highly reliable at providing spatial location data, but they suffer from shortcomings when it comes to the acquisition of kinematic quantities [3]. Above all, the application of such equipment requires controlled conditions, numerous markers, and cameras, as well as the involvement of complex algorithms for feedback [40]. On the other hand, the dynamic sports performance environment imposes the adaptability of complex motor patterns.