## 1 Introduction  
Monitoring athletes' well-being is a common practice in high-performance sport to optimize the training process and performance during the competition [1]. Neuromuscular fatigue (NMF) can be defined as a reduction in the maximal voluntary force that a muscle group can generate. The fatigue generated by the training and insufficient recovery can influence team sports performance, especially during an intense competitive period [2]. If the fatigue is excessive and not enough focus is placed on the recovery, the risk of injury or illnesses arises [3]. The authors suggest that post-competition recovery of 48 h is a minimum period to restore the testosterone-cortisol ratio [4], but there is a possibility that even 4-5 days may be needed to fully recover after an intense competition [4, 5]. Thus, monitoring fatigue may be crucial as it can lead to an increased availability of the players and subsequently influence a team's chance of success [6, 7]. It is especially important in team sports which involve frequent competition and traveling that may result in accumulating fatigue over time. Apart from physiological factors, the psychological factors should also be taken into consideration. Mental fatigue may impair physical performance, and observing fluctuations in mood, emotions and perceived stress can be valuable information for coaches of an athlete's individual response to training [8, 9]. Monitoring fatigue during the competitive season is a common practice that takes place in team sports. The trend of collecting athletes' monitoring data within team sports tends to increase and the practitioners are recommended to use simple, valid and reliable solutions to monitor athletes' well-being and prescribe training [10]. Practitioners usually introduce various methods to monitor training load and fatigue in athletes [11; 12]. Subjective monitoring tools (e.g., wellness questionnaires, session rating of perceived exertions) can be introduced separately [1; 13; 14] or with the addition of objective assessments (e.g., strength and power testing, GPS monitoring) in an integrated approach [8; 15]. Until now, the strength and conditioning coaches have been surveyed several times about their monitoring procedures [16; 17; 18]. 84% of practitioners tend to introduce subjective questionnaires, 61% of practitioners introduce neuromuscular performance testing and more than a half (54%) use vertical jump testing [16]. Also, the latest survey by [PERSON] et al. indicated that a countermovement jump (CMJ) is the most frequently (used by 92% of practitioners) used test for jump performance assessment [18]. CMJ is reliable [19] and sensitive in monitoring neuromuscular status [20] and may be more suitable to use than other vertical jumping tests such as squat jump or drop jump [21]. It was proved to be useful in team sports involving powerful actions such as sprinting or jumping [17; 22; 23], and tracking the average CMJ height may be more appropriate than the highest CMJ height to monitor NMF [20]. However, the authors suggested that this marker of NMF should not be introduced in relation to endurance runners as it shows the lack of sensitivity [24]. As these kinds of measurements are frequently implemented, the idea of injury risk during the testing procedures could be raised. So far, researchers have not examined extensively the potential risk of injury during testing procedures of CMJ, and no specific relationship was found in squat jump or depth jump testing in regards to knee or low back injury [25]. Despite being a popular tool to monitor NMF [16; 17; 18], the authors identified the lack of method standardization for CMJ as the testing procedures seem to be carried out with different technical execution [26]. It is important to select appropriate tests for a given population of the athletes, and testing within strength and conditioning should be simple and serve a purpose. Practitioners need to know why they introduce a given test and how it should be conducted to maximize its utility [27; 28].