## 5 Discussion
Researchers in this field have started to develop additional unique tests in this area as well [2, 19], and their use is also important, including continued thinking and development of additional unique tests [47, 51]. Development of such unique tests should include preliminary research to assess their reliability and validity, including comparisons to existing standard tests, like those presented in this article. At a later stage, new tests should be applied to a broad range of basketball players, to ascertain differences by age, gender, and on-court positions, among professional and amateur players, if applicable [19, 39, 45, 51, 71, 103]. Moreover, a number of tests assess athletes' upper body explosive strength (such as the 1-RM bench press test). These were not reviewed in this article as these skills are less frequently used in basketball. Efforts have been made to create tests that specifically assess lower limb explosive power among basketball players [2, 5]. Although studies indicate correlations between vertical and horizontal power [103, 105, 116], the scientific literature lacks specific tests for examining this power in combined vertical and horizontal movements [1, 32, 117]. In a study on handball players [108], no association was observed between CMJ tests and the players' time in the air--an action that entails both horizontal and vertical movements. As such, CMJ may not be a reliable tool for predicting jumping ability specific to handball players. On the other hand, a different study revealed a strong connection between CMJ outcomes and the volleyball jump serve, which also combines both horizontal and vertical components, similar to the spike jump in basketball [105]. As such, connections among these variables seem to differ from sport to sport, and perhaps even among athletes with different levels of development. Moreover, it is unclear as to whether CMJ test protocols and others can reliably predict specific basketball jumping abilities (e.g., jumping time when leaping up toward the basket on one leg in various specific jumping styles while holding the ball). Additional examples of inadequate tests can be seen in a number of intervention studies relating to ball games. While the outcomes of these studies indicate improvements in maximal sprint, strength, glyometric, and complex training, as seen in CMJ performance assessments [1, 104, 118, 119], it is unclear whether these improvements can be transferred to additional game situations, such as basket penetrating and layups. Indeed, transferring physical improvements seen in training to actual ball games is not easy to assess--as additional factors must be addressed, such as players' technical abilities and complex interactions. Since the main factor for assessing basketball players' capabilities is their anaerobic elastic system, tests that examine their anaerobic glycolytic energy system are less relevant. Tests should specifically focus on players' lower limb explosive power, such as the 5/10 m sprint test rather than the 20 m test. Moreover, it seems that while multiple tests exist, there is no standardization of these assessment tools--nationally or internationally. For example, while the horizontal and vertical drop jump tests may offer important tools for assessing basketball players' glyometric and jump height abilities, drop height and jump height are not always identical and, as such, could result in different measurements [92, 93]. Additional limitations of the existing tests can be seen in tests such as the spike jump that combines both horizontal and VJ capabilities, as differences in players' shoulder joint flexibility may impact the outcomes of the test and hinder the ability to reliably compare athletes' measurements [105]. Examining the vertical jump height of basketball players is crucial for understanding their physical capabilities. In basketball, athletes commonly use jump tests to assess the reactive power in their legs.