Development of complex executive function over childhood: Longitudinal growth curve modeling of performance on the Groton Maze Learning Task.

This longitudinal study modeled children's complex executive function (EF) development using the Groton Maze Learning Task (GMLT). Using a cohort-sequential design, 147 children (61 males, 5.5-11 years) were recruited from six multicultural primary schools in Melbourne and Perth, Australia. Race/ethnicity data were not available. Children were assessed on the GMLT at 6-month intervals over 2-years between 2010 and 2012. Growth curve models describe age-related change from 5.5 to 12.5 years old. Results showed a quadratic growth trajectory on each measure of error-that is, those that reflect visuospatial memory, executive control (or the ability to apply rules for action), and complex EF. The ability to apply rules for action, while a rate-limiting factor in complex EF, develops rapidly over early-to-mid childhood.

How Reliable and Valid are Dual-Task Cost Metrics? A Meta-analysis of Locomotor-Cognitive Dual-Task Paradigms.

OBJECTIVE: To assess the retest reliability, predictive validity, and concurrent validity of locomotor and cognitive dual-task cost (DTC) metrics derived from locomotor-cognitive dual-task paradigms. DATA SOURCES: A literature search of electronic databases (PubMed, PsycINFO, MEDLINE, CINAHL, and Scopus) was conducted on May 29th, 2021, without time restriction. STUDY SELECTION: For 1559 search results, titles and abstracts were screened by a single reviewer and full text of potentially eligible papers was considered by 2 independent reviewers. 25 studies that evaluated retest reliability, predictive validity, and concurrent validity of locomotor-cognitive DTC in healthy and clinical groups met inclusion criteria. DATA EXTRACTION: Study quality was assessed using the Consensus-Based Standards for the Selection of Health Measurement Instrument checklist. Data relating to the retest reliability, predictive validity, and concurrent validity of DTC were extracted. DATA SYNTHESIS: Meta-analysis showed that locomotor DTC metrics (intraclass correlation coefficient [ICC]=0.61, 95% confidence interval [CI; 0.53.0.70]) had better retest reliability than cognitive DTC metrics (ICC=0.27, 95% CI [0.17.0.36]). Larger retest reliability estimates were found for temporal gait outcomes (ICC=0.67-0.72) compared with spatial (ICC=0.34-0.53). Motor DTC metrics showed weak predictive validity for the incidence of future falls (r=0.14, 95% CI [-0.03.0.31]). Motor DTC metrics had weak concurrent validity with other clinical and performance assessments (r=0.11, 95% CI [0.07.0.16]), as did cognitive DTC metrics (r=0.19, 95% CI [0.08.0.30]). CONCLUSIONS: Gait-related temporal DTC metrics achieve adequate retest reliability, while predictive and concurrent validity of DTC needs to be improved before being used widely in clinical practice and other applied settings. Future research should ensure the reliability and validity of DTC outcomes before being used to assess dual-task interference.

Cognitive and Motor Therapy After Stroke Is Not Superior to Motor and Cognitive Therapy Alone to Improve Cognitive and Motor Outcomes: New Insights From a Meta-analysis.

OBJECTIVE: To evaluate whether cognitive and motor therapy (CMT) is more effective than no therapy, motor therapy, or cognitive therapy on motor and/or cognitive outcomes after stroke. Additionally, this study evaluates whether effects are lasting and which CMT approach is most effective. DATA SOURCES: AMED, EMBASE, MEDLINE/PubMed, and PsycINFO databases were searched in October 2022. STUDY SELECTION: Twenty-six studies fulfilled the inclusion criteria: randomized controlled trials published in peer-reviewed journals since 2010 that investigated adults with stroke, delivered CMT, and included at least 1 motor, cognitive, or cognitive-motor outcome. Two CMT approaches exist: CMT dual-task ("classical" dual-task where the secondary cognitive task has a distinct goal) and CMT integrated (where cognitive components of the task are integrated into the motor task). DATA EXTRACTION: Data on study design, participant characteristics, interventions, outcome measures (cognitive/motor/cognitive-motor), results and statistical analysis were extracted. Multilevel random effects meta-analysis was conducted. DATA SYNTHESIS: CMT demonstrated positive effects compared with no therapy on motor outcomes (g=0.49; 95% confidence interval [CI], 0.10, 0.88) and cognitive-motor outcomes (g=0.29; 95% CI, 0.03, 0.54). CMT showed no significant effects compared with motor therapy on motor, cognitive, and cognitive-motor outcomes. A small positive effect of CMT compared with cognitive therapy on cognitive outcomes (g=0.18; 95% CI, 0.01, 0.36) was found. CMT demonstrated no follow-up effect compared with motor therapy (g=0.07; 95% CI, -0.04, 0.18). Comparison of CMT dual-task and integrated revealed no significant difference for motor (F1,141=0.80; P=.371) or cognitive outcomes (F1,72=0.61, P=.439). CONCLUSIONS: CMT was not superior to monotherapies in improved outcomes after stroke. CMT approaches were equally effective, suggesting that training that enlists a cognitive load per se may benefit outcomes.

Home-based (virtual) rehabilitation improves motor and cognitive function for stroke patients: a randomized controlled trial of the Elements (EDNA-22) system.

BACKGROUND: Home-based rehabilitation of arm function is a significant gap in service provision for adult stroke. The EDNA-22 tablet is a portable virtual rehabilitation-based system that provides a viable option for home-based rehabilitation using a suite of tailored movement tasks, and performance monitoring via cloud computing data storage. The study reported here aimed to compare use of the EDNA system with an active control (Graded Repetitive Arm Supplementary Program-GRASP training) group using a parallel RCT design. METHODS: Of 19 originally randomized, 17 acute-care patients with upper-extremity dysfunction following unilateral stroke completed training in either the treatment (n = 10) or active control groups (n = 7), each receiving 8-weeks of in-home training involving 30-min sessions scheduled 3-4 times weekly. Performance was assessed across motor, cognitive and functional behaviour in the home. Primary motor measures, collected by a blinded assessor, were the Box and Blocks Task (BBT) and 9-Hole Pegboard Test (9HPT), and for cognition the Montreal Cognitive Assessment (MoCA). Functional behaviour was assessed using the Stroke Impact Scale (SIS) and Neurobehavioural Functioning Inventory (NFI). RESULTS: One participant from each group withdrew for personal reasons. No adverse events were reported. Results showed a significant and large improvement in performance on the BBT for the more-affected hand in the EDNA training group, only (g = 0.90). There was a mild-to-moderate effect of training on the 9HPT for EDNA (g = 0.55) and control (g = 0.42) groups, again for the more affected hand. In relation to cognition, performance on the MoCA improved for the EDNA group (g = 0.70). Finally, the EDNA group showed moderate (but non-significant) improvement in functional behaviour on the SIS (g = 0.57) and NFI (g = 0.49). CONCLUSION: A short course of home-based training using the EDNA-22 system can yield significant gains in motor and cognitive performance, over and above an active control training that also targets upper-limb function. Intriguingly, these changes in performance were corroborated only tentatively in the reports of caregivers. We suggest that future research consider how the implementation of home-based rehabilitation technology can be optimized. We contend that self-administered digitally-enhanced training needs to become part of the health literacy of all stakeholders who are impacted by stroke and other acquired brain injuries. Trial registration Australian New Zealand Clinical Trials Registry (ANZCTR) Number: ACTRN12619001557123. Registered 12 November 2019, http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378298&isReview=true.

Constraints on visual exploration of youth football players during 11v11 match-play: The influence of playing role, pitch position and phase of play.

Visual exploratory action, in which football players turn their head to perceive their environment, improves prospective performance with the ball during match-play. This scanning action, however, is relevant for players throughout the entire match, as the information perceived through visual exploration is needed to guide movement around the pitch during both offensive and defensive play. This study aimed to understand how a player's on-pitch position, playing role and phase of play influenced the visual exploratory head movements of players during 11v11 match-play. Twenty-two competitive-elite youth footballers (M = 16.25 years) played a total of 1,623 minutes (M = 73.8). Inertial measurement units, global positioning system units and notational analysis were used to quantify relevant variables. Analyses revealed that players explored more extensively when they were in possession of the ball, and less extensively during transition phases, as compared to team ball-possession and opposition ball-possession phases of play. Players explored most extensively when in the back third of the pitch, and least when they were in the middle third of the pitch. Playing role, pitch position and phase of play should be considered as constraints on visual exploratory actions when developing training situations aimed at improving the scanning actions of players.

A systematic review of the technology-based assessment of visual perception and exploration behaviour in association football.

To visually perceive opportunities for action, athletes rely on the movements of their eyes, head and body to explore their surrounding environment. To date, the specific types of technology and their efficacy for assessing the exploration behaviours of association footballers have not been systematically reviewed. This review aimed to synthesise the visual perception and exploration behaviours of footballers according to the task constraints, action requirements of the experimental task, and level of expertise of the athlete, in the context of the technology used to quantify the visual perception and exploration behaviours of footballers. A systematic search for papers that included keywords related to football, technology, and visual perception was conducted. All 38 included articles utilised eye-movement registration technology to quantify visual perception and exploration behaviour. The experimental domain appears to influence the visual perception behaviour of footballers, however no studies investigated exploration behaviours of footballers in open-play situations. Studies rarely utilised representative stimulus presentation or action requirements. To fully understand the visual perception requirements of athletes, it is recommended that future research seek to validate alternate technologies that are capable of investigating the eye, head and body movements associated with the exploration behaviours of footballers during representative open-play situations.

No evidence that visual exploratory activity distinguishes the super elite from elite football players.

Visual exploratory activities (VEA) refer to head and body movements that football players make prior to receiving the ball to search possibilities for action. VEA is considered a key performance indicator that differentiates the skill level of players. This study revisited whether VEA also distinguishes super elite, award winning players from their elite teammates without awards. To this end, video footage from the men's UEFA Champions League season 2018-2019 featuring the super elite players (n = 18) and the elite players (n = 18) was analyzed. To reduce the potential differences in match dynamics as much as possible, the selected players in the two groups were of the same team, playing the same match, in the same positioning line. VEA (i.e. frequency per unit time) during the penultimate and final pass prior to ball reception and performance (i.e. percentages of adequate ball contacts and subsequent actions) were compared between the two groups of players using ANOVA and Mann-Whitney tests, respectively. In addition, hierarchical stepwise regression analyses were conducted to explore the degree to which VEA was predicted by group and subsequent performance. The results showed that the players had higher VEA during the final pass (M = 0.45) than the penultimate pass (M = 0.41). There were no significant differences in VEA or performance between the two groups. Also, the regression analyses did not deliver significant models. We conclude that with partial control for match dynamics, no evidence emerged to support that VEA distinguishes super elite players from elite football players.

The efficacy of dance interventions for the activity and participation of individuals with cerebral palsy - a systematic review and meta-analysis.

PURPOSE: The aim of this review was to examine the efficacy of dance interventions for individuals with cerebral palsy (CP), measured at any level of the International Classification of Functioning, Disability and Health (ICF). METHODS: A systematic review and meta-analysis was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A comprehensive search of peer-reviewed articles was performed using six electronic databases. RESULTS: Fourteen studies were included in this review, nine of which were also included in the meta-analysis. The meta-analyses yielded a large overall effect for cognitive, motor, and social-emotional function outcomes, with a high degree of heterogeneity between outcome effects, attributable to differences in study design. CONCLUSION: Although recent studies provide support for the acceptance and efficacy of dance interventions for people with CP, the systematic review revealed significant limitations in study design (only 2 randomised control trials). High-quality research that measures outcomes across all dimensions of the ICF, and particularly at the level of participation, are needed to improve the level of empirical support for dance-based interventions.

Movement- and step-based dance practice for cerebral palsy have a positive impact on walking/gait, balance/postural control, and range of motion.Dance programs should move beyond a traditional focus on body structure and function, placing participation at the forefront of the program.Rehabilitation professionals should consider forming partnerships with stakeholders, addressing their goals, experiences, and challenges, with dance as a feasible and important option for participation-based practice.

Locomotor-cognitive dual-tasking in children with developmental coordination disorder.

Introduction: Children with Developmental Coordination Disorder (DCD) demonstrate deficits in predictive motor control and aspects of cognitive control compared with their typically developing (TD) peers. Adjustment to dynamic environments depends on both aspects of control and the deficits for children with DCD may constrain their ability to perform daily actions that involve dual-tasking. Under the assumption that motor-cognitive integration is compromised in children with DCD, we examined proportional dual-task costs using a novel locomotor-cognitive dual-task paradigm that enlisted augmented reality. We expect proportional dual-task performance costs to be greater for children with DCD compared to their TD peers. Methods: Participants were 34 children aged 6-12 years (16 TD, 18 DCD) who walked along a straight 12 m path under single- and dual-task conditions, the cognitive task being visual discrimination under simple or complex stimulus conditions presented via augmented reality. Dual-task performance was measured in two ways: first, proportional dual-task costs (pDTC) were computed for cognitive and gait outcomes and, second, within-trial costs (p-WTC) were measured as the difference on gait outcomes between pre- and post-stimulus presentation. Results: On measures of pDTC, TD children increased their double-limb support time when walking in response to a dual-task, while the children with DCD increased their locomotor velocity. On p-WTC, both groups increased their gait variability (step length and step width) when walking in response to a dual-task, of which the TD group had a larger proportional change than the DCD group. Greater pDTCs on motor rather than cognitive outcomes were consistent across groups and method of dual-task performance measurement. Discussion: Contrary to predictions, our results failed to support dramatic differences in locomotor-cognitive dual-task performance between children with DCD and TD, with both groups tending to priorities the cognitive over the motor task. Inclusion of a within-trial calculation of dual-task interference revealed an expectancy effect for both groups in relation to an impending visual stimulus. It is recommended that dual-task paradigms in the future continue to use augmented reality to present the cognitive task and consider motor tasks of sufficient complexity to probe the limits of performance in children with DCD.

The Relationship Between Neck Strength and Sports-Related Concussion in Team Sports: A Systematic Review With Meta-analysis.

OBJECTIVE: We aimed to quantify the relationship between neck strength and sports-related concussion (SRC) for athletes participating in team sports. DESIGN: Etiology systematic review with meta-analysis. LITERATURE SEARCH: PubMed, PsycINFO, MEDLINE, CINAHL, CENTRAL, and Scopus were searched on March 17, 2022, and updated on April 18, 2023. STUDY SELECTION CRITERIA: Team sports where an opponent invades the player's territory (eg, football, rugby, basketball) that reported at least 1 measure of neck strength, and 1 measure of SRC incidence, using cohort, case-control, or cross-sectional study designs. The Newcastle-Ottawa scale was used to assess risk of bias; certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation approach. DATA SYNTHESIS: Studies were summarized qualitatively and quantitatively. To understand the relationship between neck strength and future SRC incidence, random-effects meta-analysis was conducted on prospective longitudinal studies. RESULTS: From a total of 1445 search results, eight studies including 7625 participants met the inclusion criteria. Five studies reported a relationship between greater neck strength or motor control and reduced concussion incidence. Pooled results from 4 studies indicated small (r = 0.08-0.14) nonsignificant effects with substantial heterogeneity (I2>90%). The considerable heterogeneity is likely a result of synthesized studies with vastly different sample characteristics, including participant age, playing level, and sports. CONCLUSIONS: There was very low-certainty evidence suggesting a small, nonsignificant relationship between greater neck strength and a lower risk of sustaining a SRC. J Orthop Sports Phys Ther 2023;53(10):1-9. Epub: 10 July 2023. doi:10.2519/jospt.2023.11727.

Does exercise affect quality of life and participation of adolescents and adults with cerebral palsy: a systematic review.

PURPOSE: Investigate the effect of exercise for adults with cerebral palsy (CP) on quality of life, participation (attendance and involvement in life situations), functional mobility, pain, fatigue, mood, and self-efficacy. METHODS: A systematic review was completed. Twelve databases were searched from inception to August 2022 for studies including participants (≥16 years) with cerebral palsy, and that evaluated an exercise intervention. Two reviewers independently assessed eligibility, risk of bias, and extracted data. RESULTS: Seventeen studies (total n = 532) were included: 12 randomised control trials, four non-randomised trials, and one single case experimental design. Interventions studied were predominantly strength, aerobic or treadmill training, dance, and swimming. No study assessed participation, pain or mood. Of two studies that assessed quality of life, one reported a positive effect on an aspect of mental health immediately after the programme finished. All studies assessed functional mobility, but only one reported a positive effect. One study assessed self-efficacy and found no effect, and another assessed fatigue and reported conflicting results. CONCLUSIONS: The effect of exercise for adults with CP, on outcomes that adults report as important to them - quality of life, participation, pain, mood, and fatigue - are unknown.IMPLICATIONS FOR REHABILITATIONTo address outcomes important to adults with cerebral palsy (CP), it is important to understand how exercise affects participation and quality of life.All modes of exercise reviewed appear safe for adults with CP and choice should be based on the client's preferences, access to services, and convenience.Addressing any needed accommodations in the environment and context is likely more important than exercise prescription parameters when tailoring exercise to meet the needs of adults with CP and sustain participation.

Effectiveness of interventions for school-aged-children and adolescents with fetal alcohol spectrum disorder: a systematic review and meta-analysis.

PURPOSE: To describe allied health and educational interventions and their effectiveness for children and adolescents with fetal alcohol spectrum disorder (FASD). To appraise the quality and strength of studies. METHODS: Electronic databases were searched between 2005 and March 2022, identifying non-pharmacological studies supporting function, activity, or participation for FASD participants aged 5-18 years using any quantitative research design. Outcomes were coded using International Classification of Functioning, Disability and Health, family of Participation Related Constructs and behaviour categories. Multi-level random-effects meta-analysis examined intervention effects. Study methodological quality was evaluated using Cochrane risk of bias tools, RoBiNT, AMSTAR 2 and NHMRC Hierarchy levels of evidence. Certainty of findings were synthesised using GRADE approach. RESULTS: The systematic review included 25 studies with 735 participants, 10 of which were analysed by meta-analysis. Body function and structure, activity, behaviour, and sense of self outcomes were pooled. A small, positive effect favouring interventions was found (g = 0.29, 95% CI = 0.15-0.43), however the GRADE certainty was rated as low. No participation outcomes were identified. CONCLUSIONS: Some interventions targeting body function and structure, activity and behaviour outcomes were effective. Evidence of interventions that support children's and adolescent's participation as an outcome is lacking.Implications for rehabilitationTo address participation outcomes for children and adolescents with fetal alcohol spectrum disorder (FASD), it is important to understand their participation needs and directly measure these.Interventions identified targeted body function and structure, activity, and behaviour outcomes.Participation outcomes of children's/adolescent's attendance, involvement and preferences were not identified.A combination of individual- and context-focused interventions is recommended to maximise rehabilitation outcomes for children and adolescents with FASD.

Reply to "Asking the Right Question Is Key to Getting a Valuable Answer".

Author response to the JOSPT Letter to the Editor-in-Chief "Asking the Right Question is Key to Getting a Valuable Answer" J Orthop Sports Phys Ther 2023;53(11):726-727. doi:10.2519/jospt.2023.0204-R.

The Effect of Feedback on Resistance Training Performance and Adaptations: A Systematic Review and Meta-analysis.

BACKGROUND: Augmented feedback is often used during resistance training to enhance acute physical performance and has shown promise as a method of improving chronic physical adaptation. However, there are inconsistencies in the scientific literature regarding the magnitude of the acute and chronic responses to feedback and the optimal method with which it is provided. OBJECTIVE: This systematic review and meta-analysis aimed to (1) establish the evidence for the effects of feedback on acute resistance training performance and chronic training adaptations; (2) quantify the effects of feedback on acute kinematic outcomes and changes in physical adaptations; and (3) assess the effects of moderating factors on the influence of feedback during resistance training. METHODS: Twenty studies were included in this systematic review and meta-analysis. This review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Four databases were searched, and studies were included if they were peer-reviewed investigations, written in English, and involved the provision of feedback during or following dynamic resistance exercise. Furthermore, studies must have evaluated either acute training performance or chronic physical adaptations. Risk of bias was assessed using a modified Downs and Black assessment tool. Multilevel meta-analyses were performed to quantify the effects of feedback on acute and chronic training outcomes. RESULTS: Feedback enhanced acute kinetic and kinematic outputs, muscular endurance, motivation, competitiveness, and perceived effort, while greater improvements in speed, strength, jump performance, and technical competency were reported when feedback was provided chronically. Furthermore, greater frequencies of feedback (e.g., following every repetition) were found to be most beneficial for enhancing acute performance. Results demonstrated that feedback improves acute barbell velocities by approximately 8.4% (g = 0.63, 95% confidence interval [CI] 0.36-0.90). Moderator analysis revealed that both verbal (g = 0.47, 95% CI 0.22-0.71) and visual feedback (g = 1.11, 95% CI 0.61-1.61) were superior to no feedback, but visual feedback was superior to verbal feedback. For chronic outcomes, jump performance might have been positively influenced (g = 0.39, 95% CI - 0.20 to 0.99) and short sprint performance was likely enhanced (g = 0.47, 95% CI 0.10-0.84) to a greater extent when feedback is provided throughout a training cycle. CONCLUSIONS: Feedback during resistance training can lead to enhanced acute performance within a training session and greater chronic adaptations. Studies included in our analysis demonstrated a positive influence of feedback, with all outcomes showing superior results than when no feedback is provided. For practitioners, it is recommended that high-frequency, visual feedback is consistently provided to individuals when they complete resistance training, and this may be particularly useful during periods of low motivation or when greater competitiveness is beneficial. Alternatively, researchers must be aware of the ergogenic effects of feedback on acute and chronic responses and ensure that feedback is standardised when investigating resistance training.

Behavioral and Neuroimaging Research on Developmental Coordination Disorder (DCD): A Combined Systematic Review and Meta-Analysis of Recent Findings.

AIM: The neurocognitive basis of Developmental Coordination Disorder (DCD; or motor clumsiness) remains an issue of continued debate. This combined systematic review and meta-analysis provides a synthesis of recent experimental studies on the motor control, cognitive, and neural underpinnings of DCD. METHODS: The review included all published work conducted since September 2016 and up to April 2021. One-hundred papers with a DCD-Control comparison were included, with 1,374 effect sizes entered into a multi-level meta-analysis. RESULTS: The most profound deficits were shown in: voluntary gaze control during movement; cognitive-motor integration; practice-/context-dependent motor learning; internal modeling; more variable movement kinematics/kinetics; larger safety margins when locomoting, and atypical neural structure and function across sensori-motor and prefrontal regions. INTERPRETATION: Taken together, these results on DCD suggest fundamental deficits in visual-motor mapping and cognitive-motor integration, and abnormal maturation of motor networks, but also areas of pragmatic compensation for motor control deficits. Implications for current theory, future research, and evidence-based practice are discussed. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, identifier: CRD42020185444.

Principles of the Guidance of Exploration for Orientation and Specification of Action.

To control movement of any type, the neural system requires perceptual information to distinguish what actions are possible in any given environment. The behavior aimed at collecting this information, termed "exploration", is vital for successful movement control. Currently, the main function of exploration is understood in the context of specifying the requirements of the task at hand. To accommodate for agency and action-selection, we propose that this understanding needs to be supplemented with a function of exploration that logically precedes the specification of action requirements with the purpose of discovery of possibilities for action-action orientation. This study aimed to provide evidence for the delineation of exploration for action orientation and exploration for action specification using the principles from "General Tau Theory." Sixteen male participants volunteered and performed a laboratory-based exploration task. The visual scenes of different task-specific situations were projected on five monitors surrounding the participant. At a predetermined time, the participant received a simulated ball and was asked to respond by indicating where they would next play the ball. Head movements were recorded using inertial sensors as a measure of exploratory activity. It was shown that movement guidance characteristics varied between different head turns as participants moved from exploration for orientation to exploration for action specification. The first head turn in the trial, used for action-orientation, showed later peaks in the velocity profile and harder closure of the movement gap (gap between the start and end of the head-movement) in comparison to the later head turns. However, no differences were found between the first and the final head turn, which we hypothesized are used mainly for action orientation and specification respectively. These results are in support of differences in the function and control of head movement for discovery of opportunities for action (orientation) vs. head movement for specification of task requirements. Both are important for natural movement, yet in experimental settings,orientation is often neglected. Including both orientation and action specification in an experimental design should maximize generalizability of an experiment to natural behavior. Future studies are required to study the neural bases of movement guidance in order to better understand exploration in anticipation of movement.

Don't Turn Blind! The Relationship Between Exploration Before Ball Possession and On-Ball Performance in Association Football.

Visual exploratory action - scanning movements expressed through left and right rotation of the head - allows perception of a surrounding environment and supports prospective actions. In the dynamically changing football environment, the extent to which exploratory action benefits a player's subsequent performance with the ball is likely influenced by how and when the exploratory action occurs. Although few studies have examined the relationship between visual exploration and on-pitch football performance, it has been reported that a higher frequency of exploratory head movement up to 10-s before receiving the ball increases the likelihood of successful performance with the ball. This study investigated the relationship between head turn frequency and head turn excursion, and how and when exploratory head movement - within 10-s before ball possession - is related to performance with the ball in 11v11 match-play. Thirty-two semi-elite football players competed in 11v11 match-play. Head turn frequency and head turn excursion before ball possession were quantified with wearable inertial measurement units, and actions with the ball were coded via notational analysis. Odds ratio calculations were conducted to determine the associations between exploration variables and on-ball performance outcomes. A total of 783 actions with the ball were analyzed. Results revealed a strong relationship between head turn frequency and head turn excursion. Further, a higher than average head turn frequency and head turn excursion before receiving the ball resulted in a higher likelihood of turning with the ball, playing a pass in the attacking direction, and playing a pass to an area that is opposite to which it was received from. The strength of these outcomes varied for different time periods before receiving the ball. When players explored their environment with higher than average head turn frequency and excursion, they used more complex action opportunities afforded by the surrounding environment. Considerations for future research and practical implications are discussed.