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.