Assessing Asymmetries in Change of Direction Speed Performance: Application of Change of Direction Deficit

Abstract

The aims of this study were to quantify asymmetries in change of direction (COD) performance via completion time and COD deficit, and determine its influence on asymmetry profiling of COD ability. A secondary aim was to evaluate the relationship between linear speed, 505 time and COD deficit. Forty-three youth netball athletes (age: 15.4 ± 1.1 years, height: 1.71 ± 0.06 m, mass: 63.3 ± 6.6 kg) performed the 505 for both left and right limbs and a 10 m sprint test. Asymmetries in 505 completion time and COD deficit were quantified for dominant (D) (faster) and non-dominant (ND) (slower) directions. Paired sample t-tests revealed significant differences between D and ND directions for 505 time and COD deficit (p < 0.0001, g = -0.53 to -0.60). Substantially greater asymmetries for COD deficit were observed compared to 505 time (p < 0.0001, g = 1.03). Only two subjects displayed an asymmetry ≥10% based on 505 times. Conversely, based on COD deficit, 21 subjects demonstrated asymmetries ≥10%. Large significant associations were observed between 505 time and COD deficit (r = 0.500-0.593, p ≤ 0.002). Large significant inverse associations were demonstrated between 10 m sprint time and COD deficit (r = -0.539 to -0.633, p ≤ 0.001) indicating faster athletes had longer COD deficits. Nine subjects were classified differently for COD ability when comparing standardized scores for 505 time versus COD deficit. Quantification of asymmetries in COD ability should be based on COD deficits; inspection of 505 times only could lead to misinterpretations of an athlete's COD symmetry and COD ability. Faster youth netball athletes demonstrate longer COD deficits, thus, researchers and practitioners are encouraged to improve their youth netball athletes' ability to rapidly decelerate, change direction and reaccelerate from 180° turns.

Strength, Jumping, and Change of Direction Speed Asymmetries Are Not Associated With Athletic Performance in Elite Academy Soccer Players

“…COD test showed a lower magnitude of asymmetry (COD5: 4.60% ± 2.51% and COD10: 3.02% ± 1.74%) in comparison to the jump and iso-inertial power tests, which is in agreement with previous research (Fort-Vanmeerhaeghe et al, 2015;Dos'Santos et al, 2018;Madruga-Parera et al, 2019). The COD tests' inability to detect asymmetries could be due to two reasons: first, there is a strong linear speed component during COD, mainly in COD10 (Madruga-Parera et al, 2019), and second, sprint times are far more replicable than power outputs during jump (Bishop et al, 2019a) or iso-inertial tests.…”

Change of direction asymmetry across different age categories in youth soccer

“…The present findings are in line with the study of Dos'Santos et al (2019b), which reported asymmetries of COD d (in the 505 COD test) on average greater than 10% in youth netball players. Moreover, the authors found that asymmetries of COD d were approximately fivefold greater than asymmetries of total time (−11.9% vs. −2.3%, respectively).…”

“…This calculation was also applied by using the same formula replacing the values with COD d (Dos'Santos et al, 2019b). Moreover, as previously proposed by Dos'Santos et al (2019b) and Trecroci et al (2020) an asymmetry threshold (AT%) was also computed for each group by the following formula:…”

“…The fact that COD deficit calculation does not include the acceleration phase would provide diverse quantification of asymmetry compared with COD total time. In this regard, Dos'Santos et al (2019b) quantified the COD asymmetry in the 505 COD test by deficit and total time according to the preferred direction in youth netball players. Beside observing meaningful differences between preferred and non-preferred directions of both COD deficit and total time, the authors also found that asymmetry percentage was greater for COD deficit than COD total time, indicating a different sensitivity between tests in detecting asymmetry-related differences.…”

Decisive Factors for a Greater Performance in the Change of Direction and Its Angulation in Male Basketball Players

“…These contradictions could be solved by introducing the concept of deficit in COD, where COD action is isolated from linear action within the tests [ 53 ]. While several studies [ 54 , 55 ] have shown the relationship of CODs to the deficit itself, no considerations have been made with linear velocity. Although some authors [ 56 ] still suggest linear velocity to be a determining factor for COD performance, high COD approaching velocities may increase the loads which the knee receives in valgus.…”