Associations between Inter-Limb Asymmetries in Jump and Change of Direction Speed Tests and Physical Performance in Adolescent Female Soccer Players

Abstract

The association between asymmetries in jump and change of direction (COD) with physical performance in several sports show inconclusive results. The purposes of this study were to: (1) measure inter-limb asymmetries in three distinct groups in adolescent female soccer players and, (2) to determine the association between inter-limb asymmetries and physical performance in different age groups. Fifty-four players were distributed in three age groups: U-18, U-16 and U-14. All of them performed a series of jumps, sprints and change of direction speed tests. Asymmetries were assessed as the percentage difference between limbs, with the equation: 100/Max value (right and left) * in value (right and left) * −1 + 100. Mean inter-limb asymmetries were 2.91%, 4.82% and 11.6% for 180° COD, single leg hop and single leg countermovement jump tests respectively, but higher percentages of asymmetries were observed in many players individually. U-18 and U-16 showed significant differences on 180° left COD compared to U-14. Effect size (ES): 0.80 and 0.74, respectively; U-18 presented differences on single left leg hop test compared to U-14, ES: −0.72; U-16 also showed differences on 40 m speed compared to U-14, ES 0.87 (All p < 0.05). Jumping and COD physical tests show asymmetries in adolescent female soccer players, but these asymmetries do not interfere with physical performance. The largest asymmetry was observed in the single leg countermovement jump, and no asymmetries between groups were found. Due to the high variability in the direction of asymmetries, it is recommended to consider players’ individual asymmetries for designing specific training programs.

Relationship between Asymmetries Measured on Different Levels in Elite Basketball Players

“…Similarly, the agreement between asymmetries in CoD and single-joint and complex movement asymmetries was also generally non-significant, with a few cases of significant but only fair levels of agreement. These results are in accordance with a previous study that measured agreement between jumping and CoD asymmetry directions in female soccer players [24]. In addition, Bishop et al [23] proved there is a substantial level of agreement (Kappa = 0.61) between squat jump and CMJ in female soccer players.…”

“…From a rehabilitation and return to play perspective, testing asymmetry with horizontal jumps has previously been widely practiced [35]. This and previous studies show that the horizontal jumping test shows similar sensitivity to the CoD test when it comes to asymmetry [24]. From that viewpoint, CoD is a more sport specific movement, especially for team sports, which makes it a suitable return to play test, same as horizontal jumps.…”

“…Only a few studies have investigated agreement in asymmetry direction between different levels of asymmetry. Padros-Mainer et al [24], with a study conducted on female soccer players, showed poor to fair levels of agreement (Kappa = −0.31-0.24) in asymmetry direction between jumps (horizontal and vertical) and change of direction. In accordance with this is the study by Kozinc and Šarabon, conducted on volleyball players, that also showed poor agreement (Kappa < 0.2) between complex movement asymmetries measured with single-leg horizontal and vertical jumps and asymmetries in CoD (90 • and 180 • ) [21].…”

“…Some research shows substantial levels of agreement between asymmetry directions measured with different tests [23]. However, previous authors suggested that asymmetry rarely favors the same side between tasks and that further investigation is needed to provide a clearer picture of the task-specific nature of asymmetries [13,21,24]. Although previous research suggests sport games which contain CoD and pivoting movement can develop sport asymmetries, the majority of asymmetry studies used a soccer population, and basketball as a sport was neglected [13].…”

Influence of 2D:4D ratio on fitness parameters and accumulated training load in elite youth soccer players

“…Other performance tests were performed separately on a daily basis and in the following order. The CMJ, ISH, ISQ and the Intermittent Fitness Test 30–15 (30-15 IFT ), the 30-15 IFT was used to estimate the VO 2max [ 36 ]. The time for the training sessions and tests was in the afternoon.…”