RESUMO
PURPOSE: The current study examined the possible relationships between one-off single night sleep metrics and subsequent kicking performance in a youth soccer context. METHODS: Twenty-eight under-17 academy players (15.9 ± 0.8 years-old) completed a kick testing protocol consisting in 20 attempts, 18 m from the goal and against a goalkeeper. Four digital video cameras (240 Hz) allowed to determine 3-D approach run, lower limb and ball velocities. Two additional cameras (60 Hz) were used to calculate 2-D mean radial error, bivariate variable error and accuracy. Over 24 h prior to testing, players were monitored by wrist actigraphy to determine their sleep indices. Self-reported sleep quality, sleepiness and chronotype scale scores (Horne and Östberg morningness-eveningness questionnaire) were also collected immediately before kicking experiment. RESULTS: Multiple linear regressions indicated that wake up time and chronotype contributed to 40% of mean radial error. Self-reported sleep quality influenced respectively on 19% and 24% of accuracy and bivariate variable error variances. Taken together self-reported sleep quality and wake up time explained 33% of accuracy (all p < 0.05). Indicators of kicking velocity were non-significantly correlated with sleep (r = -0.30-0.29; p > 0.05). CONCLUSION: One-off sleep measures showed some sensitivity to acutely detect inter-individual oscillations in kicking performance. Low perceived sleep quality, later wake up time and a chronotype toward evening preference seem either related to immediately subsequent worst ability of ball placement when kicking. Monitoring sleep-wake transition and perceived sleep quality may be important to help prevent acute performance declines in targeting the goal during kick attempts from the edge of penalty area.
Better acute sleep quality, earlier wake up time and preference toward morning activities presented positive influences on soccer kicking parameters, specifically related to ball placement in upper corners of the goalpost;Kicking velocity was minimally influenced by sleep quality and duration while either kicking accuracy or velocity characteristics were similar between youth players that slept for more or less than 7, 8 or 8.4 hours in an assessment night;In a youth soccer context, inter-individual one-off sleep measures were associated with some ensuing skill-related outputs, thereby monitoring sleep parameters on an individual basis may assist in preventing suboptimal performance occurrences.
