A Systematic Review of the Different Calculation Methods for Measuring Jump Height During the Countermovement and Drop Jump Tests

Abstract

Background The heights obtained during the countermovement jump and drop jump tests have been measured by numerous studies using different calculation methods and pieces of equipment. However, the differences in calculation methods and equipment used have resulted in discrepancies in jump height being reported. Objectives The aim of this systematic review was to examine the available literature pertaining to the different calculation methods to estimate the jump height during the countermovement jump and drop jump. Methods A systematic review of the literature was undertaken using the SPORTDiscus, MEDLINE, CINAHL, and PubMed electronic databases, with all articles required to meet specified criteria based on a quality scoring system. Results Twenty-one articles met the inclusion criteria, relating various calculation methods and equipment employed when measuring jump height in either of these two tests. The flight time and jump-and-reach methods provide practitioners with jump height data in the shortest time, but their accuracy is affected by factors such as participant conditions or equipment sensitivity. The motion capture systems and the double integration method measure the jump height from the centre of mass height at the initial flat foot standing to the apex of jumping, where the centre of mass displacement generated by the ankle plantarflexion is known. The impulse-momentum and flight time methods could only measure the jump height from the centre of mass height at the instant of take-off to the apex of jumping, thus, providing statistically significantly lower jump height values compared with the former two methods. However, further research is warranted to investigate the reliability of each calculation method when using different equipment settings. Conclusions Our findings indicate that using the impulse-momentum method via a force platform is the most appropriate way for the jump height from the instant of take-off to the apex of jumping to be measured. Alternatively, the double integration method via a force platform is preferred to quantify the jump height from the initial flat foot standing to the apex of jumping.

The Countermovement Rebound Jump: Between-Session Reliability and a Comparison With the Countermovement and Drop Jump Tests

“…The overestimation could be because the FT method assumes that the COM position at the take-off instant is identical to landing, which rarely happened because more flexed lower extremities were required to attenuate the landing force. Numerous studies have acknowledged this phenomenon (9,28,36,39). However, if practitioners have no other option but to use this method (because of equipment availability) verbal cues such as "fully extend your lower limb joints during take-off and landing instants," aiming to minimize factors that artificially extend the time in the air, are suggested (39).…”

“…Owing to some anthropometric effects such as foot length or lower limb configuration, individual subjects might raise their COM heights to different extents before the take-off instant; thus, JH in this study was defined as the COM displacement from the COM height at the instant of take-off to the peak COM height (i.e., apex) during jumping (36,39). The equation and process of the FT and IM methods when calculating the JH values were identical to those discussed in a recent study by Xu et al (39). The DI method integrated the net vertical GRF data twice using the trapezoid rule from the movement initiation to the landing to acquire the COM displacement-time data on a sample-by-sample basis (27,28).…”

“…Jumping is a commonly performed movement action in various sports, which requires the coordination of multiple joints and muscles (5,9,36). Although numerous jump types exist, the countermovement jump (CMJ) and drop jump (DJ) are 2 of the most frequently used jumps in practice (5,21,28,36,37,39) and represent slow and fast stretch-shortening cycle (SSC)-based movements, respectively. During the CMJ, athletes perform a countermovement to a self-selected degree of hip and knee flexion, immediately followed by a propulsive extension of the lower extremities, aiming to jump as high as possible (23).…”

“…Jump height is probably the most common metric that previous studies have used to evaluate an athlete's jump performance (6,9,23,28). Several calculation methods have been proposed to derive JH during jump actions (39). The 4 main methods are as follows: (a) flight time (FT) method, (b) impulse-momentum (IM) method, (c) double integration (DI) method, and (d) 3-dimensional motion capture systems (3DMCS) (28,36,39).…”

“…Several calculation methods have been proposed to derive JH during jump actions (39). The 4 main methods are as follows: (a) flight time (FT) method, (b) impulse-momentum (IM) method, (c) double integration (DI) method, and (d) 3-dimensional motion capture systems (3DMCS) (28,36,39). During the CMJ, when quantifying JH from the center of mass (COM) height at the instant of take-off to the peak COM height, Slomka et al (34) found that all numerical methods (i.e., FT, IM, and DI methods) reported excellent reliability (coefficient of variation [CV] # 0.13%; intraclass correlation coefficient [ICC] $ 0.90) when being assessed on FP.…”