Drop Jump Asymmetry is Associated with Reduced Sprint and Change-of-Direction Speed Performance in Adult Female Soccer Players

Abstract

Studies that examine the effects of inter-limb asymmetry on measures of physical performance are scarce, especially in adult female populations. The aim of the present study was to establish the relationship between inter-limb asymmetry and speed and change-of-direction speed (CODS) in adult female soccer players. Sixteen adult players performed a preseason test battery consisting of unilateral countermovement jump (CMJ), unilateral drop jump (DJ), 10 m, 30 m, and 505 CODS tests. Inter-limb asymmetry was calculated using a standard percentage difference equation for jump and CODS tests, and Pearson’s r correlations were used to establish a relationship between asymmetry and physical performance as well as asymmetry scores themselves across tests. Jump-height asymmetry from the CMJ (8.65%) and DJ (9.16%) tests were significantly greater (p < 0.05) than asymmetry during the 505 test (2.39%). CMJ-height asymmetry showed no association with speed or CODS. However, DJ asymmetries were significantly associated with slower 10 m (r = 0.52; p < 0.05), 30 m (r = 0.58; p < 0.05), and 505 (r = 0.52–0.66; p < 0.05) performance. No significant relationships were present between asymmetry scores across tests. These findings suggest that the DJ is a useful test for detecting existent between-limb asymmetry that might in turn be detrimental to speed and CODS performance. Furthermore, the lack of relationships present between different asymmetry scores indicates the individual nature of asymmetry and precludes the use of a single test for the assessment of inter-limb differences.

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

“…No significant relationships were present between asymmetry scores, highlighting the independent nature of the selected tests in elite youth male soccer players ( Table 2). This finding is supported by previous studies (Loturco et al, 2018;Bishop et al, 2019c), which stated a lack of relationships between different asymmetry scores in both female and male elite senior soccer players. Furthermore, in a recent study, Bishop et al (2018a) observed that when comparing asymmetry scores across multiple tests levels of agreement were typically poor.…”

Change of Direction Performance Is Influenced by Asymmetries in Jumping Ability and Hip and Trunk Strength in Elite Basketball Players

“…This observation could be explained by local strength asymmetries show higher magnitudes. Negative influence of asymmetry in vertical drop jump height and COD performance (180 • turn test) (r = 0.66, p < 0.01 and 0.52, p < 0.05; depending on the side of the turn) was found by Bishop et al [21]. Also, using horizontal jumps to assess asymmetries, Madruga-Parera et al [38] found much lower correlations (r = 0.32 and 0.31, p <0.05) between asymmetry in horizontal jumping length (SLLJ) and COD performance (V-cut and 180 • turn test).…”

“…By contrast, few studies have found a significant correlation between global asymmetry in jumping tests and COD performance. Studying female soccer players, Bishop et al [21] found a significant positive correlation between inter-limb asymmetry in single-leg depth jump height and performance in 505 COD test on left (r = 0.66, p < 0.01) and right (r = 0.52, p < 0.05) side. Another study that reported a relationship between asymmetry and performance was of Maloney et al [22], that explained 63% (p < 0.001) of variance of COD performance with leg stiffness and height asymmetry during vertical depth jump.…”

Inter-limb asymmetries are associated with decrements in physical performance in youth elite team sports athletes

“…In contrast, Bishop et al [7] showed that jump height asymmetry (12.5%) from the SLCMJ was associated with slower 5m (r = 0.49; p < 0.05), 10m (r = 0.52; p < 0.05) and 20m (r = 0.59; p < 0.01) sprint performance in youth female soccer players. In addition, Bishop et al [18] showed that drop jump asymmetries were associated with slower acceleration, speed and COD performance in adult female soccer players. Specifically, jump height asymmetry was correlated with 30m (r = 0.58; p < 0.05) and 505 (r = 0.52-0.66; p < 0.05), and reactive strength index asymmetry was correlated with 10m (r = 0.52; p < 0.05) and 505 on both limbs (r = 0.54-0.55; p < 0.05).…”