Effects of a Congested Fixture Period on Speed and Power Performance of Elite Young Soccer Players
in International Journal of Sports Physiology and PerformancePurpose: To investigate the effects of a match-congested period on straight and curve sprint performance, change of direction (COD) speed and deficit, vertical jumping ability, and half-squat (HS) mean propulsive power (MPP) output in young soccer players. Methods: A total of 15 under-20 elite male soccer players participated in 14 matches over 8 weeks. The following assessments were performed before and after the congested fixture period: squat and countermovement jumps, 17-m linear sprint, curve sprint test for the “good” (CSGS) and “weak” (CSWS) sides, modified 17-m Zigzag test, and HS MPP. Magnitude-based inferences and a paired t test were used to analyze pre–post changes in the assessed variables. Results: Very likely (P < .05) decreases were noticed in 17-m sprint velocity (effect size [ES] [90% confidence limit; CL], −0.56 [−0.32 to −0.81]) and CSGS (ES [90% CL], −0.72 [−0.40 to 1.03]) after the 8-week period. A possible but nonsignificant impairment was revealed in CSWS (ES [90% CL], −0.18 [0.03 to −0.39]), and countermovement jump (ES [90% CL], −0.21 [−0.54 to 0.12]). Zigzag velocity (ES [90% CL], −2.90 [−2.45 to −3.36]) and COD deficit (ES [90% CL], 0.86 [0.52 to 1.20]) were almost certainly and significantly (P < .05) reduced and increased, respectively, after the match-congested period. An almost certain and significant (P < .05) reduction was found in HS MPP (ES [90% CL], −1.18 [−0.76 to −1.61]). Conclusions: Straight and curve sprint velocity, COD speed and deficit, and HS MPP were impaired after the match-congested period. Vertical jump height was possibly decreased. Seasonal phases comprising high volumes of soccer-specific training and competition seem to be detrimental to speed–power qualities in under-20 elite soccer players.
Freitas and Alcaraz are with the UCAM Research Center for High Performance Sport, Catholic University of Murcia, UCAM, Murcia, Spain. Freitas, Pereira, Reis, Fernandes, and Loturco are with the NAR—Nucleus of High Performance in Sport, São Paulo, Brazil. Freitas, Pereira, Azevedo, and Loturco are with the Dept of Human Movement Sciences, Federal University of São Paulo, Santos, Brazil. Alcaraz is also with the Faculty of Sport Sciences, Catholic University of Murcia, Murcia, Spain. Loturco is also with the University of South Wales, Pontypridd, Wales, United Kingdom.
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