Author(s): YOSHIOKA, H., YOSHIDA, T., TANIGAWA, S., Institution: UNIVERSITY OF TSUKUBA, Country: JAPAN, Abstract-ID: 2046

INTRODUCTION:
Change-of-direction (COD) performance in soccer is determined by both sprint performance and the capacity to decelerate and reaccelerate. COD deficit (CODD), calculated as COD-test time minus an equivalent sprint time, is used as a COD-specific indicator accounting for sprint speed (1). Countermovement jump (CMJ) and rebound jump (RJ) are commonly used to assess Stretch–Shortening Cycle SSC function and have been reported to be associated with sprint and COD performance. However, their relationship with CODD remains unclear. Therefore, this study examined associations between CODD and sprint performance in collegiate female soccer players.
METHODS:
Fifty-three collegiate female soccer players performed linear sprints (5, 10, 20, and 30 m), pro-agility (PA), CMJ, and RJ. CODD was calculated as PA time minus 20-m sprint time, and RJ-index (jump height / contact time). Pearson’s correlations were calculated among variables. Participants were classified into FAST and SLOW groups based on 20 m sprint time. Subsequently, group differences in performance variables were examined using independent samples t-tests. Correlations between CODD and CMJ/RJ variables (RJ-index, RJ jump height, and RJ contact time [RJCT]) were examined within each group.
RESULTS:
CODD was negatively correlated with 5–10 m sprint times and positively correlated with RJCT and PA time; PA time was positively correlated with sprint times. The FAST group showed better jump performance (CMJ, RJ-index and RJ jump height) and faster PA time than the SLOW group but exhibited a larger CODD. Within the FAST group, CODD was associated with RJ-index and RJCT.
CONCLUSION:
CODD was associated with short-distance sprint performance, suggesting incomplete independence from sprint performance. Higher approach velocities in high sprint-performing players may increase braking and reacceleration demands, yielding larger CODD (2). CODD was associated only with RJCT in the overall sample, whereas within the FAST group it was associated with both RJ-index and RJCT. In the present sample, RJ-index was strongly correlated with RJ jump height (r = .869), suggesting that RJ-index may have been strongly influenced by RJ jump height. Therefore, among high sprint-performing players, rapid force production within a short ground contact time may be particularly important for COD efficiency.
In collegiate female soccer players, CODD was influenced by short-distance sprint performance; however, SSC performance was associated with CODD within the high sprint-performing group, suggesting their involvement in efficient change-of-direction performance.
REFERENCE
(1) Nimphius S, Callaghan SJ, Bezodis NE, Lockie RG (2016). J Strength Cond Res, 30(11), 3024-3032.
(2) Roso-Moliner A, Mainer-Pardos E, Bishop C, Gonzalo-Skok O (2024). Int J Sports Physiol Perform, 19(12), 1374-1380.