# Reaction Time and Postural Control Under Dual-Task Conditions in Brazilian Jiu-Jitsu Athletes
## 1 Introduction  
Daily living activities require a fundamental level of postural control [1, 2]. Maintaining correct body posture and balance during rapid movements or sports is crucial for physically fit individuals, particularly those engaged in martial arts such as Judo [3], Taekwon-do [4, 5, 6], Karate, Krav Maga, or Brazilian Jiu-Jitsu [7]. In the last decade, there has been a significant rise in the popularity of Brazilian Jiu-Jitsu, due to the success of Brazilian athletes in mixed martial art events [8]. The primary goal in Brazilian Jiu-Jitsu is to force the opponent into submission using chokeholds, joint locks (e.g., elbow, knee, and ankle locks), and pressure techniques. When a submission is not achieved, the match is decided based on points awarded for specific techniques (such as guard passes, mounts, and back control), or by the referee's decision in the case of a draw [9, 10, 11, 8]. Brazilian Jiu-Jitsu athletes must be in exceptional physical condition, possessing a broad range of physical attributes [11]. Key factors for success include aerobic power for sustaining high-intensity efforts throughoutthe match [12]; muscle power for effective throwing techniques; muscular endurance; reaction time for anticipating opponent moves; and flexibility, which plays a critical role in both attack and defense situations [8; 9]. In [PERSON]'s [10] systematic review which describes the physical and physiological profiles of Brazilian Jiu-Jitsu athletes, reaction time was described only in two papers. Moreover, during the literature review, a limited number of studies were found that describe the characteristics of postural control among combat sport athletes. This observation is noteworthy because maintaining a stable body posture is equally challenging when executing defensive and counterattacking techniques in conditions of significant instability [13]. Recent studies show that martial art training can improve postural control not only in individuals with neurological disorders [14] but also in healthy adults [15]. The long-term practice of combat sports, such as Judo [16], Karate [17], and Taekwon-do [18], leads to changes in postural control. Interestingly, junior athletes and untrained individuals typically exhibit poorer balance, as assessed in both static and dynamic tests, compared to senior, elite athletes [19]. Furthermore, differences in postural control are observed early in training, with adult practitioners displaying superior balance abilities compared to their same-aged, physically active peers [1]. Many studies have suggested that postural control changes are more pronounced in sport-specific positions than in basic ones like bipedal standing [20]. In static conditions (bipedal, quiet standing), elite judokas, surfers, and dancers did not achieve better postural measurements than the control groups [21; 22]. However, these athletes demonstrated superior postural control during dynamic tasks or when performing dual-task exercises [23]. The dual-task paradigm, where athletes perform physical and cognitive tasks simultaneously, is a well-established method for assessing the interaction between motor control and cognitive functions. This paradigm is especially relevant in combat sports, where quick reactions and balance are paramount [24; 25]. Studies involving Taekwon-do athletes have shown that dual-task conditions can negatively affect both motor and cognitive performance. However, targeted dual-task training has proven effective in improving performance in both static and dynamic tasks [26]. By incorporating dual-task training into combat sports, athletes can enhance their ability to divide attention between cognitive and motor tasks, which leads to better postural stability and more responsive dynamic reactions [27]. Moreover, dual-task performance can serve as an indicator of cognitive function and motor adaptation, suggesting its value in evaluating the training levels and postural control strategies of combat sport athletes [28; 29].