Introduction
Basketball players rely on power-related attributes to perform key movements during on-court performance (26,33,39). However, the effectiveness of methods to assess sport-specific, power-related attributes in basketball has yet to be fully identified, implemented, and evaluated. Misunderstanding of power in basketball centers on translating the underlying concept of power, measured in joules per second (J·s−1) (34), to physical attributes relating to acceleration, speed, agility, and jump performance. In this regard, the common testing procedures typically adopted by basketball practitioners address general outcomes dependent upon power, yet precise knowledge on the specific attributes of power (e.g., reactive strength) contributing to basketball performance is still in its infancy. A large number of different power-based tests have been employed in practice and in research, which makes it difficult for basketball practitioners to select appropriate test protocols for optimal assessment of power-related attributes. A review of literature to identify game-specific, power-related attributes in basketball is required to develop a test battery predicated on evidence-based decision-making. Therefore, the aims of this review were to: (a) identify key power-related attributes important in basketball; (b) investigate the suitability of common and novel power-related tests; and (c) recommend future research directions and best practice approaches for basketball practitioners.
Importance of Power in Basketball
Time–motion analyses indicate that basketball is a highly intermittent, team sport, involving a dynamic array of multidirectional movements (9–11,75,77). These movement requirements highlight the importance of power for on-court success in basketball given every change in movement (e.g., sprinting and jumping) and/or direction (e.g., cutting) involves precise sequencing of force transmission generating large amounts of power to decelerate and re-accelerate the body. Table 1 provides an overview of the types and frequencies of player movements performed during men’s basketball game-play as shown in time–motion studies.
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Table 1.: Movement frequencies performed during basketball game-play as identified through time–motion research (mean ± SD).
Changes in movement type and intensity typically occur every 1–2 seconds during men’s basketball game-play (8,9,11,75,77). Frequent changes in movement type and direction occur in a multidirectional setting where players often change planes of movement quickly. For example, on defense, a player typically engages in a blend of linear backpedaling, lateral shuffling, and rotational movements before attempting a high-intensity vertical jump to defend against an opponent's shot attempt. Such movement patterns underpin the importance of assessing basketball-specific movements in a multidirectional fashion, in isolation, and embedded in integrated movement sequences. It appears that basketball players competing at higher playing levels may execute more acceleration, decelerations, changes in direction, and high-intensity activity during game-play, emphasizing the importance of developing power-related attributes to cope with the demands of competition. Specifically, international-level men basketball players performed 10% more overall movements and 25% more high-intensity activity (sprinting, high-intensity shuffling, jumping, positioning, setting picks, and intense static actions) movements than national-level players during games (8). Furthermore, power-related attributes such as sprinting and high-intensity shuffling have differentiated between basketball players competing at different playing levels (10).
Power Assessment in Basketball and Commonly Used Tests to Assess Power-Related Attributes in Basketball
A power-based basketball testing battery needs to assess linear speed (11,57,75), lateral speed, change-of-direction (COD) performance (85), and vertical and horizontal jumping ability (100). Each of these movements has been identified as important for on-court basketball performance. In addition to movement type, game-specific distances and repetitions for each movement also warrant consideration. The following section explores various tests used to assess these attributes in basketball (see summary in Table 2).
Table 2.: Summary of commonly used tests to assess power-related attributes in basketball.
Commonly Used Tests to Assess Power-Related Attributes in Basketball
Linear Speed Testing
Linear sprint speed is the ability to generate high levels of power over each stride to cover as much distance as possible in the shortest time (59). Speed testing for basketball has generally been evaluated at distances between 5 and 36 m (26–28,30,38,39,46). The ecological validity of tests close to or exceeding the length of a basketball court (28 m) is questionable given players rarely execute sprints over these distances during games. This suggestion is reflected in the literature, where Hoffman et al. (39) reported a weak relationship between 27-m sprint performance and playing time (r = −0.24) in Division I collegiate men basketball players (n = 15). Considering in-game sprint bouts typically last between 0.5 and 2.0 seconds, relating to distances of 3–10 m (9,57,77), and most sprints are less than 20 m (75), the most appropriate distances to assess game-specific linear sprint speed and acceleration are likely between 5 and 10 m (10,19,37,78). In this regard, senior international players (n = 15; 25 ± 3 years) performed 10–17% better in 5 and 10-m linear sprint splits than junior international players (n = 15; 18 ± 3 years) (10). Basketball players adopt sprint patterns characterized by a relatively lower center of gravity accompanied with reduced knee flexion and knee lift compared with short-distance track events (99). This sprint pattern allows players to transition from linear sprints to COD maneuvers in response to opponent actions and as a result track speed does not necessarily translate to game speed in basketball (98). Consequently, speed assessments in basketball should include basketball-specific, multidirectional movement sequences.
Multidirectional and Change-of-Direction Testing
Execution of repeated short burst and multiplanar movements during basketball implies that power testing should incorporate high-intensity running efforts over short distances with stop-start and multidirectional elements. Change-of-direction performance involves coordinated neuromuscular activity that rapidly decelerates the body without losing balance and generates medial-lateral ground reaction forces to propel the body in a new direction (85). Although linear sprints and COD performance involve expressions of speed (76), COD performance is an independent motor skill (90). Consequently, proficiency in linear or COD speed does not automatically translate to the other (90). Given the frequent changes in movement intensities and directions players experience throughout a typical basketball game, COD performance is regarded as a key physical component for on-court performance (10,75,77). As directional changes in basketball are often accompanied by changes in movement (e.g., sprinting into defensive shuffling), tests measuring COD performance need to accommodate the multidirectional requirements and relevant movement types performed during basketball. There is limited research assessing multidirectional abilities in basketball players, with only the agility T-test shown to discriminate between basketball players from different playing levels (10,26).
Agility T-Test
The agility T-test (Figure 1) has been frequently used by basketball coaches and researchers to assess COD performance (3,10,27,79). The agility T-test is comprised of multidirectional, basketball-specific movements with 4 directional changes involving sprinting, lateral shuffling, and backpedaling (79). The agility T-test is considered a valid tool for assessing leg speed, leg power, and changing directions, supporting its use in assessing power in a multidirectional manner (64). Evidently, elite national and international men basketball players performed 6.2% better on the agility T-test (n = 8; 9.21 ± 0.24 seconds) than domestic university players (n = 8; 9.78 ± 0.59 seconds) (26). Another study reported senior players (n = 15; 25 ± 3 years; 9.99 ± 0.40 seconds) performed 5.4% better on the agility T-test than junior players (n = 15; 18 ± 3 years; 10.53 ± 0.67 seconds) in national Tunisian men’s basketball teams (10).
Figure 1.: Layout of the agility T-test.
Although the agility T-test possesses adequate discriminative validity to assess multidirectional movement performance in basketball, one of the key limitations in its application to measure COD speed involves the substantial influence of linear and shuffling speeds on overall test time. Specifically, agility T-test performance was highly correlated with 5-m (r = −0.83) and 10-m (r = −0.92) sprint speed and shuffling speed (r = −0.75) in sub-elite men basketball players (n = 9) (66). Furthermore, the agility T-test features distances exceeding those typically covered during basketball game-play across each sprint and shuffling bout (75). Given the prevalence of directional changes in basketball and common sprint distances covered, an alternative assessment measuring multidirectional performance in basketball players is warranted.
Lane Agility Test
The lane agility test is a multidirectional test administered as part of the National Basketball Association (NBA) Draft Combine protocol (81) (Figure 2). Although the lane agility test is conducted annually for NBA talent identification, it is unclear whether it can discriminate between playing levels in basketball. The lane agility test is a reliable test (Intraclass correlation coefficients [ICC] = 0.99, coefficient of variation [CV] = 8.7%) but is weakly correlated with rankings of on-court movement ability provided by coaches in Division III collegiate teams (men: n = 12, ρ = 0.51; women: n = 12, ρ = 0.41) (14). Moreover, varied relationships have been observed between lane agility test performance and playing time in collegiate basketball players (r = −0.59 to −0.12) (25,54). Collectively, the available evidence highlights some issues on the practical utility of the lane agility test in measuring multidirectional movement ability relevant to on-court basketball performance.
Figure 2.: Layout of the lane agility test.
Although the lane agility test assesses multidirectional movement performance and involves common movements in basketball (sprinting, shuffling, and backpedaling), the limited research supporting its use may be related to the extended distance and duration of the test (14,25,54). Specifically, mean shuffling distances in elite basketball players are approximately 1.8–2.2 m (75), which is less than shuffling distances in the lane agility test (3.7 m). Further research is required to clarify the utility of the lane agility test in assessing multidirectional movement performance in basketball including its ability to discriminate between players from high and lower playing levels and in quantifying changes in players within and between seasons.
505 Change-of-Direction Test
The 505 Change-of-Direction Test (505 COD Test) is useful for measuring COD performance in basketball (32,49,87). The 505 COD Test involves a 15-m sprint, followed by a 180° turn, after which players re-accelerate for an additional 5 m (Figure 3). A flying start is used in the 505 COD Test whereby timing commences at the 10-m mark and ends after the 5-m re-acceleration. In comparison with the time profile of other agility tests (lasting up to 13 seconds) (26,48), the typical duration of the 505 COD Test is relatively short (approximately 2–3 seconds) (47,84) and representative of high-intensity cuts that occur during basketball. However, use of a flying start omits the initial acceleration phase executed from a standing start. Thus, performance during the 505 COD Test likely reflects in-game cutting maneuvers initiated when moving at higher velocities rather than from a stationary position.
Figure 3.: Layout of the 505 change-of-direction test.
Collegiate basketball players performed the 505 COD Test 5.4% faster than recreational players (89), demonstrating the potential use of the 505 COD Test to differentiate between playing levels. When comparing faster and slower performers of the 505 COD Test in elite women basketball players, 6 faster players (0.42 ± 0.03 seconds) had substantially shorter contact times during directional changes than 6 slower players (0.47 ± 0.04 seconds) (84). The shorter ground contact time during directional changes indicates a better COD performance where players use less time to recover and regain position on defense and perform quicker maneuvers on offense. Practitioners can use the information provided by 505 COD Test as an indicator of the ability of players to perform basketball-specific maneuvers such as a 180° backdoor cut to sprint away from defensive pressure. In addition, the 505 COD Test is a practical tool to measure ambidexterity between the 2 cutting sides. Professional, women basketball players (n = 15) exhibited greater ambidexterity and less lower-body sidedness than collegiate women players (n = 15) (82). Furthermore, 505 COD Test performance in previously injured limbs was 2% slower than uninjured limbs in recreational team sport players (47). Hence, ambidexterity measures in the 505 COD Test may be useful to assess functional imbalances potentially predisposing players to a higher risk of injury and as a measure of readiness when returning from injury.
When selecting multidirectional and COD tests, practitioners need to consider the specificity of the movement patterns involved to those encountered in basketball. Although the traditional agility T-test and lane agility test assess multidirectional movement performance, they contain movement distances longer than those typically performed during basketball game-play. The lane agility test and the agility T-test provide a global assessment of multidirectional movement proficiency with test performance influenced by the ability to generate speed in linear and lateral directions (66). Consequently, the 505 COD Test offers an independent assessment of COD performance and permits detection of functional imbalances between limbs. Nevertheless, future research is required to examine tests that better isolate COD performance and lateral movement abilities in basketball. Tests of this nature will enable improved diagnostic and training prescription for basketball players.
Jump Testing
Vertical jumping is one of the key movements performed during basketball game-play (11,75). A successful vertical jump depends on efficient neuromuscular coordination to produce high levels of power to overcome gravity and propel a player vertically. Basketball players typically perform 40–50 jumps per game (11,57,75), generating force rapidly to execute various tasks such as rebounding, blocking opponent shot attempts, and creating elevation for a jump shot. In this regard, more accurate shooters release the ball at a greater jump height underpinning the importance of vertical jumping on offense (42,65). A high vertical jump is advantageous for basketball players for many game tasks such as gaining possession of the ball when rebounding, creating opponent turnovers by intercepting the ball, or disrupting opponent shot attempts.
Although vertical jump testing is regarded as a standard assessment in basketball testing batteries (5,63,100), there are no studies detailing the specific utility and relevance of various procedures used during vertical jump testing. The 4 common vertical jump tests in basketball are the squat jump, countermovement jump without arm swing, Sargent jump, and one-step jump.
Squat Jump
The squat jump measures the capacity to generate power using concentric-only muscular actions (12). The squat jump involves performing a high-intensity jump from a static squat position similar to jumping for a rebound from an isometric box-out position during basketball game-play. Players squat to a predetermined depth, hold the position for 1–3 seconds, and then perform a maximal jump strictly void of any countermovement with hands held on the waist. Jump height can be derived from flight time using a contact mat or force platform. On a force platform, additional measures of peak force and rate of force development can be acquired.
In practice, the squat jump test alone provides little information; however, it can be a useful diagnostic tool to guide training prescription when used with other jump measures (55). More precisely, evaluating squat jump and countermovement jump performance in combination allows basketball practitioners to derive an eccentric utilization ratio. Calculated as countermovement jump height divided by squat jump height, the eccentric utilization ratio describes the efficiency of a player in using the stored elastic energy via the stretch-shortening cycle to augment jump performance (55). Given frequent dynamic movements are performed in basketball, the capacity to maximize re-utilization of elastic energy is a highly desirable attribute in players. As a result, the squat jump used in conjunction with the countermovement jump can assist in prescribing gym-based training approaches necessary to increase power-related attributes.
Countermovement Jump Without Arm Swing
The countermovement jump without arm swing is an eccentric-concentric jump performed with hands held on the waist and assesses lower-body power augmented by the stretch-shortening cycle. Players squat and jump explosively while minimizing the amortization phase, which is the transition between eccentric-to-concentric contractions (40). By eliminating upper-body contributions, the countermovement jump without arm swing measures lower-body power that is fundamental to other jump variations (e.g., Sargent jump, one-step jump). The ability to achieve a high vertical jump with minimal upper-body contribution is important for execution of a jump shot where players are required to create high elevation off the ground with minimal contribution from arm swing.
Performed on a force platform, the countermovement jump without arm swing can be used to inform training prescription by reflecting the underlying degree of neuromuscular fatigue (20,22). During states of fatigue or incomplete recovery, athletes exhibit an altered jump pattern signified by an increased contraction time and decreased flight time (23,24). Given the reliance on jump ability during basketball game-play, the countermovement jump without arm swing may be useful given the movement sequence involved resembles some in-game tasks such as shooting where players are required to perform jump maneuvers without contributions from the upper-limbs.
Sargent Jump
The Sargent jump (73) is a countermovement jump executed from a stationary position with arm swing to propel the body upwards generating additional propulsion (2,58). Use of upper-limbs is considered a more natural movement than without arm swing for basketball players as it simulates various scenarios in basketball (100). Moreover, the Sargent jump is a reliable field test (ICC = 0.96, CV = 3.0%) commonly implemented via the jump-and-reach method using a yardstick (50). The Sargent jump test is low cost compared with approaches using force platforms. Additionally, the vanes of the yardstick provide an external focus of attention that can increase vertical jump height compared with jump measurements without a target (95).
Although the Sargent jump demands increased upper-body coordination (15), it is relevant for basketball players proficient in coordinating lower and upper-body movement sequences in combination as part of regular jump-and-reach tasks performed during game-play. Given the high relevance of the Sargent jump in basketball (44,70–72), it may be useful in talent identification or team selection where better performers will likely have an increased chance of success during basketball-specific tasks such as rebounding. This test may also be a useful tool for ongoing player physical evaluation of lower-body power generation using a game-specific movement pattern for monitoring across seasonal phases (off-season, pre-season, and competition) and subsequent seasons.
One-Step Jump
One-step jump tests involve a player transferring horizontal momentum to augment vertical power. Commonly measured using the jump-and-reach method via a yardstick, the one-step jump is one of the most important abilities in basketball where players are often required to execute a maximal jump transitioning from a stepping motion (e.g., performing a layup on the fast break or blocking an opponent's shot attempt on defense) (100). Given there is a direct transfer of the one-step jump to basketball game-play, high competency is likely advantageous for playing success. Accordingly, national and international-level basketball players generated a 9% higher one-step jump than domestic university players (26).
When selecting vertical jump tests, practitioners should consider the specific movements and outcomes of each assessment. For example, the squat jump is used to assess lower-body power in isolation from a static position. However, when combining the squat jump with the countermovement jump, these tests become a diagnostic tool to facilitate training prescription. Specifically, players with superior squat jump ability relative to countermovement jump ability may require training to improve stretch-shortening cycle actions, whereas players with poor squat jump performance relative to the countermovement jump may benefit from targeted strength training of the lower-body musculature to improve overall force generation. Conversely, the Sargent jump and one-step jump tests are suitable for talent identification to separate higher- and lower-level players in team selection processes. Furthermore, the jump-and-reach method adopted in the Sargent jump and one-step jump tests is cost effective, easy to administer, and more closely mimics in-game movements, which carries greater ecological validity and practicality than other approaches. Furthermore, despite the high frequency of lateral movements in basketball (75), no studies have measured power generated in the frontal plane. This deficiency is important to consider given the frequent execution of high-intensity shuffling during defense to maintain position in front of opponents attacking the basket.
Novel Tests to Assess Power in Basketball
Encouraged by increasing knowledge of in-game demands and advancements in technology, a more pragmatic approach to testing power-related attributes is needed in basketball. Novel approaches to assess power-related attributes in basketball are needed to address gaps in practice and enhance game-specific application. A selection of novel tests assessing power-related attributes in basketball is detailed in Table 3.
Table 3.: Summary of novel tests to assess power-related attributes in basketball.
Sprint Momentum
Given basketball players possess diverse anthropometric dimensions, it is important to consider player body size when assessing speed performance (13,37,69). For instance, height and body mass ranged between 180–221 cm and 76–121 kg in 60 elite men basketball players, respectively (63). Therefore, in addition to assessing performance time during linear sprint testing, sprint momentum should also be measured. Sprint momentum is quantified as the product of velocity and body mass, representing linear sprint speed relative to body mass. Although sprint momentum is yet to be explored in basketball players, it discriminated elite from sub-elite rugby players (6), indicating potential utility in team sport settings. Sprint momentum is important when basketball players are required to overcome physical contact from an opponent during offensive or defensive maneuvers such as high-speed transition opportunities to attack the basket. Under these circumstances, a greater sprint momentum creates difficulties for opponents to intervene (6).
Standing Long Jump
Standing long jump is a test for horizontal power generation (4) and likely reflects the ability of a player to cover large distances in the sagittal plane on the perimeter or in the post position. Efficient maneuvering of the center of mass in these instances will allow a player to evade defenders during dribble penetration or perform high-intensity jumps attacking the basket during layup or dunk attempts. In practice, coaches can also use the standing long jump as an indicator of quickness, as players demonstrating high proficiency in this test are likely to be competent in executing explosive short burst movements on the court.
Modified Agility T-Test
The modified agility T-test (Figure 4) may counter the limitations of the traditional agility T-test given it contains basketball game-specific movement distances (66,74). More precisely, the modified agility T-test requires players to sprint a total distance of 20 m including a maximum of 5 m before changing direction (74). These distances are 50% less than the distances covered in the traditional agility T-test and more closely replicate movement patterns performed in elite basketball given players typically sprint or shuffle for less than 5 m before changing movement type (75). Furthermore, the modified agility T-test appears reliable (ICC = 0.92–0.95; CV% = 2.6–2.7%) and less influenced by linear sprint speed than the traditional agility T-test possessing weak correlations (r = 0.22–0.34) with 10-m sprint time in 86 recreational team sport players (74). However, more research is needed to confirm the reliability and validity of the modified agility T-test in assessing multidirectional performance in basketball players.
Figure 4.: Layout of the modified agility T-test.
Change-of-Direction Deficit
Although the 505 COD Test measures COD performance, only 31% of the total 505 COD Test time is spent performing the directional change (62). Hence, linear speed constitutes the majority of performance time during the 505 COD Test (62). The change-of-direction deficit (CODD) was proposed to better isolate COD performance and is calculated as the difference between the performance time measured during the 505 COD Test and flying 10-m sprint time during separate linear sprints (61). Consequently, CODD measures the additional time taken to execute a change in direction compared with sprinting linearly. Change-of-direction deficit was weakly correlated with linear sprint speed (r = −0.11 to 0.10); conversely, 505 COD Test time was strongly correlated with linear sprint speed (r = 0.52–0.70) in 17 sub-elite team sport players (61). Therefore, CODD could provide a better indication of COD performance than the traditional 505 COD Test.
Change-of-direction deficit provides a game-specific assessment of COD performance in basketball players. For instance, movements performed during the 505 COD Test are evident in basketball when a player defensively closes out on the perimeter and then changes direction quickly to recover from an opponent's dribble penetration or reacts to an opponent's cutting actions. Offensively, movement requirements in the 505 COD Test are evident when players perform aggressive cuts to beat a defender to open positions on the court, or quickly change direction after setting a screen and sprint towards the basket for scoring opportunities. Although COD performance is an important power-related attribute in basketball, various fitness attributes including isometric strength (85) likely underpin the ability of players to change direction quickly.
Isometric Midthigh Pull
The isometric midthigh pull (IMTP) is a multijoint, functional, isometric strength test. The IMTP is set up with an immovable barbell placed at a height replicating the power position in weightlifting movements. From this position, players perform a maximal effort pull, standing on top of a force platform. The key advantage of the IMTP is the direct measure of power-related attributes concerning force and time. Specifically, the IMTP generates a force–time graph for practitioners to quantify peak force and maximal rate of force development (mRFD). The relevance of maximal isometric strength testing has been established in a variety of sports including weightlifting (7), rugby (91), wrestling (56), and cycling (86). Although IMTP assessment has received limited research attention in basketball (84,85), IMTP peak force was strongly correlated with COD performance time (r = −0.85) in 12 elite women basketball players (85). In team sport settings, mRFD derived during the IMTP is moderately to highly correlated with jump height (r = 0.39) and 10-m sprint time (r = −0.66) in 39 professional rugby league players (92). Given the IMTP directly quantifies rate and volume of force generation in a position similar to defensive and box out stances in basketball, it is regarded as a useful tool to measure peak force and mRFD abilities important during common, power-driven movements such as sprinting, accelerating, and jumping (88).
Basketball practitioners can use IMTP data to infer the strength capacity and explosiveness of a player. Specifically, high levels of strength, indicated by large peak force, are likely advantageous when experiencing physical contact during offensive and defensive positioning. Meanwhile, explosive strength, quantified by mRFD (58), is typically registered in the initial 50 ms of a muscular contraction (1). Explosive strength is a highly desirable power attribute that is important during execution of explosive short burst efforts underpinning various game movements. The ability to exert large forces quickly will allow more rapid deceleration, re-acceleration, and changes in direction during defensive and offensive movements, and repeated jumps.
However, assessment of mRFD is challenging given high variability in outcome measures as a function of methodological variations (e.g., force platform sampling at 700 Hz vs. 1,000 Hz) (41,58,80,92). Consequently, impulse represented as an integral of force multiplied by time has emerged as a more reliable measure for quantifying explosiveness. Impulse correlated highly with jump height in elite volleyball players (r = 0.59–0.80) (68) and athletes experienced with vertical jumping (r = 0.68–0.73) (67). Impulse demonstrated greater test reliability than mRFD (mRFD: ICC = 0.83–0.90; impulse: ICC = 0.95–0.98) during IMTP testing in collegiate athletes (21). Furthermore, the capacity to generate large impulses (product of force and time) influences maximal sprinting speed; an athletic ability characterized by limited duration for force application (16,93,94). For example, stronger recreational team sport athletes (soccer, basketball, and netball players) during IMTP testing were faster and generated 7% greater vertical impulse when changing directions than weaker athletes, underpinning the importance of impulse during COD (83).
Reactive Strength Testing
The stretch-shortening cycle enhances power generation during dynamic sporting activities. Reactive strength, defined as the ability to quickly transition from eccentric to concentric contractions (96), can be used as a measure of “elasticity.” A common indicator of reactive strength is the reactive strength index. The reactive strength index is calculated as jump height divided by ground contact time (31), where a shorter duration between eccentric and concentric contractions, and higher jump height, contribute to superior test outcomes. Given the quick contractions of stretch-shortening cycle movements, reactive strength is viewed as an important attribute influencing jumping and high-speed sprinting performances (97). The reactive strength index is commonly obtained through depth jump and repeated jump tests, which are useful assessment tools for measuring stretch-shortening cycle ability.
Depth Jump
The depth jump test has been primarily used to evaluate reactive strength (29,31). To execute the depth jump test, players step from a box at predetermined heights (e.g., 0.30, 0.45, 0.60, 0.75 m), land briefly and then immediately jump as high as possible (96). The resultant jump height is recorded and deemed valid if the contact time was under 200 ms (96). The depth jump quantifies the ability to tolerate increasing stretch load, placing players under maximal stretch conditions. The depth jump can be used as a diagnostic tool where the step height producing the greatest reactive strength index can be implemented during training drills (17,51). Adequate depth jump performance is a highly desirable attribute for basketball players to tolerate high stretch loads during quick directional changes, transitioning between high-intensity movements, and repeated effort maneuvers such as multiple jumps for contesting shot attempts or rebounds during a game.
Repeated Jump
The 10-to-5 repeated jump test is used to measure reactive strength (35). In the 10-to-5 repeated jump test, participants perform 11 maximal effort countermovement jumps on a contact mat system aiming to reduce contact time between jumps. Contact times of less than 250 ms are required for jumps to qualify for further analysis. At the end of the trial, the 5 highest jumps are summed to generate a repeated reactive strength score. A concern with applying the 10-to-5 repeated jump test is the high frequency of jumps not indicative of basketball game-play. Consequently, we propose a modified version including 5 jumps, with the 3 best jumps with contact times of less than 250 ms used for analysis.
Reactive strength testing using the repeated jump method is a useful proposition given the relevance of the movement sequences for basketball players. Repeated jumping is important during scenarios where multiple jumps are performed in sequence such as rebounding and contesting shot attempts. The repeated jump test may be suitable to assess the ability of basketball players to minimize ground contact time while maintaining jump height during repeated jump efforts.
Lateral Bound
A high frequency of lateral movements performed during basketball game-play has been documented in time–motion studies (57,75). In laboratory settings, defensive shuffling produces the greatest medial-lateral forces of all common basketball movements, up to double the body mass of players (53). However, there are no field tests in basketball that directly measure force generation in a medial-lateral direction. Based on the standing long jump test that measures horizontal jumping distance in the sagittal plane, we propose a lateral bound test where players jump and take-off with the outside leg while landing on the inside leg for one maximal bound. With the medial aspect of the take-off foot on the start line prior the jump, the bound distance is measured with a measuring tape from the start line to the lateral aspect of the landing foot. Basketball practitioners can also use this test to detect asymmetrical power imbalances by assessing bilateral performance.
Given the size of a player will likely influence performance during the lateral bound test, relative measures accounting for limb-length and body mass will likely be necessary. In players possessing similar lower-limb lengths, the player who covers a larger distance will possess a greater advantage on defense compared with the player who covered less distance. Moreover, a heavier player who can generate a similar lateral step distance to players with a lower body mass will be able to better withstand physical contact during defense. Therefore, lateral bound testing should account for differences in: (a) limb length by dividing lateral step distance by lower-limb length; and (b) body mass by multiplying lateral step distance by body mass (18).
The ability to cover a large distance per step is important to generate high velocity in the frontal plane and will allow players to execute explosive short bursts to evade defenders on the perimeter or quickly maneuver to contain opponent dribble penetrations. Acceleration is governed primarily by the distance a player is able to cover per stride (43,60). Conversely, generating large amounts of force, a product of mass and acceleration, to inflict or withstand physical contact against opponents is a frequent event in basketball. Body mass is an important anthropometric consideration when evaluating power performance as the ability to cover large distances with high body mass is a desirable attribute for basketball players.
Recommendations for Power Testing in Basketball
The ability to perform basketball-specific power-based movements such as jumping, sprinting, defensive shuffling, and cutting is important for player success in basketball (75). Some existing power-related tests have limitations that diminish their ecological validity and ease of implementation. We have rated existing and novel tests on their scientific support, basketball-specific applications, and practicality (Table 4). Using the available evidence, we recommend use of the following tests to assess power-related attributes in basketball: (a) 10-m linear sprint with 5 and 10-m split times recorded, (b) modified agility T-test, (c) 505 COD test, (d) lateral bound, (e) Sargent jump, (f) one-step jump test, and (g) IMTP. Depending on the outcomes sought from testing, basketball practitioners are encouraged to select one or more of these tests when assessing players.
Table 4.: Scores and scoring criteria for commonly used and novel tests for assessing power-related attributes in basketball.*†
Based on the evidence provided by time–motion studies (8,9,11,75), linear speed is best measured at distances of 5 and 10 m as they reflect typical sprint distances covered without a COD during game-play. When conducting linear sprint testing, elapsed sprint time and sprint momentum should be determined. Sprint momentum accounts for the diverse body dimensions across playing positions in basketball. Quantifying sprint momentum provides basketball practitioners with a more accurate depiction of linear speed performances where players of larger body size will not be disadvantaged with slower test times. Limitations to the linear sprint test largely center on the financial cost and technical expertise required to operate electronic timing gates for accurate assessments. For teams without access to electronic timing gates, handheld timers may be employed with knowledge that this approach is dependent on operator ability and produces consistent (ICC = 0.98; CV = 1.7%) but 4.9% faster times than electronic timing gates (36,52).
Given basketball requires the expression of power in multiple directions, the modified agility T-test elicits various basketball-specific movements in multiple directions. The modified agility T-test can be used to assess the ability to transition between high-intensity movements in sagittal and frontal planes. It is important to acknowledge that although the modified agility T-test involves multidirectional movements indicative of basketball game-play, it does not provide an isolated measure of COD performance. The CODD is recommended to provide a targeted assessment of COD performance in basketball players. Practitioners can also use CODD to detect bilateral imbalances that may place players at an increased risk of lower-limb injury (47).
Given the large volume of defensive shuffling performed during basketball game-play, a targeted approach is necessary to measure horizontal-oriented power-related attributes in the frontal plane. We propose a novel maximal lateral bound test that measures lateral movement abilities. Players who can cover greater distances in a single bound are likely to perform lateral defensive maneuvers more effectively during basketball game-play. The lateral bound test is user-friendly as it can be implemented with a measuring tape without imposing high financial, expertise, and time demands.
Vertical jump ability is another key power-related attribute that influences skills (e.g., shooting and rebounding) performed during basketball game-play. The Sargent jump and one-step jump are highly relevant field-tests recommended for assessing vertical jump ability in basketball players. The Sargent jump and one-step jump tests replicate movement patterns frequently encountered during game-play and can discriminate between basketball players of differing physical abilities (10,26,37). The vertical jump offers a user-friendly and relatively low-cost method that provides consistent jump measurements. Where available, force profiling through squat jump and countermovement jump without arm swing are valuable for player monitoring and may be used to detect early signs of overtraining and inform training program prescription. A primary constraint of these jump assessments is the high level of expertise needed to acquire and analyze the data.
Although limited by cost and expertise requirements, the IMTP remains a useful test for advanced player profiling. The IMTP provides a safe and quick appraisal of maximal strength, which normally involves excessive loading of the spine. The IMTP is unique considering its ability to measure speed of force generation and strength capacity in a body position that replicates typical stances performed in basketball. The specific outcome measures of peak force and impulse can be used to profile player training status and subsequently prescribe training interventions targeting individual needs.
A multifaceted approach for assessing power-related attributes in a basketball-specific manner is based on movements performed during game-play. Given basketball teams are often under high time pressures with limited resources and in some cases expertise, practitioners need to consider the cost and time requirements when implementing a test battery to assess power-related attributes. Although it is outside the scope of this review, other tests assessing expressions of power with cognitive components (e.g., reaction to stimuli, decision-making tasks) carry high translation to game-specific scenarios in basketball. For instance, the Reactive Shuttle Test is used in the NBA Draft Combine and involves players accelerating in reaction to a stimulus before executing rapid changes in direction. Future basketball research is encouraged examining the reliability and validity of power-related tests with cognitive components such as the Reactive Shuttle Test. Furthermore, the recommended tests in this review are provided globally across all players in a team and wider investigation is needed to identify power-related tests that are most relevant for each position.
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