Running together influences where you look.

To read this article, you have to constantly direct your gaze at the words on the page. If you go for a run instead, your gaze will be less constrained, so many factors could influence where you look. We show that you are likely to spend less time looking at the path just in front of you when running alone than when running with someone else, presumably because the presence of the other runner makes foot placement more critical.

That's out! How expert umpires make leg-before-wicket judgements in cricket.

Despite evidence that elite-level cricket umpires are highly accurate in making leg-before-wicket (LBW) judgements, there is limited understanding as to how they make these judgements. In this study, we explored the explicit LBW decision-making expertise of elite-level cricket umpires (N = 10) via 10 individual semi-structured interviews. Using thematic analysis, we aimed to identify the sources of information that umpires incorporate into their decision-making process. Results indicated that umpires engage in intentional pre-delivery information-gathering to guide their expectations, and to set context-specific parameters as to what would constitute an LBW dismissal. Not only do umpires use information about the ball trajectory, but they also use additional information about the condition of the pitch, the action-capabilities and susceptibilities of players, and the unique requirements of different match formats. Umpires reported employing a gaze-anchor strategy when gathering information for each delivery and described the process of this information as initially intuitive, before engaging in deeper post-hoc reasoning. Findings highlight the importance of including contextual information when exploring officials' decisions and may inform future training interventions for cricket umpires.

Eye Tracking to Assess the Functional Consequences of Vision Impairment: A Systematic Review.

BACKGROUND: Eye tracking is a promising method for objectively assessing functional visual capabilities, but its suitability remains unclear when assessing the vision of people with vision impairment. In particular, accurate eye tracking typically relies on a stable and reliable image of the pupil and cornea, which may be compromised by abnormalities associated with vision impairment (e.g., nystagmus, aniridia). OBJECTIVES: This study aimed to establish the degree to which video-based eye tracking can be used to assess visual function in the presence of vision impairment. DATA SOURCES: A systematic review was conducted using PubMed, EMBASE, and Web of Science databases, encompassing literature from inception to July 2022. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS: Studies included in the review used video-based eye tracking, included individuals with vision impairment, and used screen-based tasks unrelated to practiced skills such as reading or driving. STUDY APPRAISAL AND SYNTHESIS METHODS: The included studies were assessed for quality using the Strengthening the Reporting of Observational Studies in Epidemiology assessment tool. Data extraction and synthesis were performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Our analysis revealed that five common tests of visual function were used: (i) fixation stability, (ii) smooth pursuit, (iii) saccades, (iv) free viewing, and (v) visual search. The studies reported considerable success when testing individuals with vision impairment, yielding usable data from 96.5% of participants. LIMITATIONS: There was an overrepresentation of conditions affecting the optic nerve or macula and an underrepresentation of conditions affecting the anterior segment or peripheral retina. CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS: The results offer promise for the use of eye tracking to assess the visual function of a considerable proportion of those with vision impairment. Based on the findings, we outline a framework for how eye tracking can be used to test visual function in the presence of vision impairment.

Are predictive saccades linked to the processing of peripheral information?

High-level athletes can predict the actions of an opposing player. Interestingly, such predictions are also reflected by the athlete's gaze behavior. In cricket, for example, players first pursue the ball with their eyes before they very often initiate two predictive saccades: one to the predicted ball-bounce point and a second to the predicted ball-bat-contact point. That means, they move their eyes ahead of the ball and "wait" for the ball at the new fixation location, potentially using their peripheral vision to update information about the ball's trajectory. In this study, we investigated whether predictive saccades are linked to the processing of information in peripheral vision and if predictive saccades are superior to continuously following the ball with foveal vision using smooth-pursuit eye-movements (SPEMs). In the first two experiments, we evoked the typical eye-movements observed in cricket and showed that the information gathered during SPEMs is sufficient to predict when the moving object will hit the target location and that (additional) peripheral monitoring of the object does not help to improve performance. In a third experiment, we show that it could actually be beneficial to use SPEMs rather than predictive saccades to improve performance. Thus, predictive saccades ahead of a target are unlikely to be performed to enhance the peripheral monitoring of target.

Identification of "sleeping" talent using psychological characteristics in junior elite ice-hockey players.

Scouts search for "sleepers" who may be initially overlooked but ultimately exceed expectations. The psychological characteristics of those players are often neglected because they are difficult to observe, but hold promise to identify sleepers given for example the self-regulation and perceptual-cognitive skills that those developing players might need to flourish. The aim of this study was to examine whether sleepers could be retrospectively identified using psychological characteristics. Ninety-five junior elite ice-hockey players (aged 15-16) were assessed on self-regulation and perceptual-cognitive skills before the yearly draft. Seventy players were drafted after the second round (37th or later). Three years later, professional scouts identified 15/70 sleepers they would now pick if given the chance. Those identified by the scouts showed higher self-regulation planning, and had distinguishable gaze behaviour (fewer fixations on more AOIs) when performing a video-based decision-making task than other late-drafted players (84.3% correct classification; R2 = .40). In addition, two latent profiles differentiated by self-regulation were found, with the profile with higher scores including 14/15 players selected by the scouts. Psychological characteristics were successful in retrospectively predicting sleepers, and may in future help scouts to make better selections of talent.

The effects of simulated vision impairment on performance in football.

Footballers with vision impairment (VI) are eligible to compete in the Para sport if they meet a minimum impairment criteria (MIC) based on measures of their visual acuity (VA) and/or visual field. Despite the requirements of the International Paralympic Committee Athlete Classification Code that each sport uses an evidence-based classification system, VI football continues to use a medical-based system that lacks evidence to demonstrate the relationship between impairment and performance in the sport. The aim of this study was to systematically simulate vision loss to establish the minimum level of impairment that would affect performance in futsal. Nineteen skilled sighted players completed tests of individual technical skill and anticipation performance under six levels of simulated blur that decreased both VA and contrast sensitivity (CS). VA needed to be reduced to a level of acuity that represents worse vision than that currently used for inclusion in VI football before meaningful decreases in performance were observed. CS did not have a clear effect on football performance. These findings produce the first evidence for the minimum impairment criteria in VI football and suggest a more severe degree of impairment may be required for the MIC.

Expert Views on Evidence-Based Classification for Goalball: A Delphi Study.

Para sport classification aims to minimize the impact of impairments on the outcome of competition. The International Paralympic Committee requires classification systems to be evidence based and sport specific, yet the sport of goalball uses a structure that is not supported by evidence demonstrating its legitimacy for competition. This study aimed to establish expert opinions on how a sport-specific system of classification should be structured in the sport of goalball. Using a three-round Delphi survey, 30 international experts expressed their views across topics linked to goalball classification. Participants were divided as to whether the current system fulfills the aim to minimize the impact of impairment on competition. Most felt that less impairment should be required to compete but that the one-class structure should remain. Experts identified measures of visual function that should be considered and 15 core components of individual goalball performance. Findings constitute a crucial first step toward evidence-based classification in goalball.

Laterality and performance: Are golfers learning to play backwards?

When using a bimanual tool to strike an object, most people place their preferred hand closer to the striking end. In sports, a player is deemed to adopt a "right- or left-handed" stance depending on the hand that is lower on the club or bat. Research has suggested there is an advantage in going against this convention by placing the preferred hand at the top in a "reversed-stance". This study aimed to establish if the reversed-stance advantage exists in golf, whether it is underpinned by the preferred hand or dominant eye, and why players adopt such a stance. We tested hand preference, eye dominance, and full swing stance in 150 golfers (30 for each handicap category) and conducted follow-up interviews with 12 reversed-stance players. Professional or category 1 golfers were 21.5 times more likely to adopt a reversed-stance. The advantage could not be explained by ambidexterity or the dominant eye but could be explained by the position of the preferred hand. Reversed-stance players cited a variety of reasons for adopting it and were more likely to display a left-hand preference. Findings offer initial evidence of a reversed-stance advantage in golf and can inform work identifying its origins and mechanisms.

Predictors of selection into an elite level youth football academy: A longitudinal study.

Talent identification in football is complex. Research regarding talent indicators that predict selection into professional academies is increasingly multi-disciplinary, though is typically cross-sectional, failing to consider whether the rate of change of those indicators influences selection. The aim of this study was to determine if longitudinal changes in talent indicators are associated with selection into a professional football academy. A total of 110 Dutch male football players (aged 8-12) playing in a youth development programme of a professional club were included in the study. Players were assessed regularly on their anthropometry, physical fitness, gross motor coordination, technical ability, and psychosocial capacities over four years. A subset of players was then selected into the academy. Cross-sectional and longitudinal analyses revealed the indicators that best predicted selection. The best indicator was the 30 m sprint speed, with prediction not improving when including other predictors or their rate of change. The individuals that the club ultimately selected at age 12 could have been predicted well above chance levels using the sprint speeds at age nine or ten. The relative consistency of the rate of improvement in indicators across participants meant that the rate at which they developed played little role in selections.

Review: Sport Performance and the Two-visual-system Hypothesis of Vision: Two Pathways but Still Many Questions.

SIGNIFICANCE: The two-visual-system hypothesis (TVSH) provides a framework for understanding the nature of the visual information athletes are likely to rely on during competition. If valid, the framework provides a valuable means of evaluating the likely efficacy of different vision training tools that claim to improve the sport performance of athletes.The TVSH has been used to explain that many of the existing methods of testing and training vision may be ineffective to improve on-field sport performance. The TVSH suggests that the visual pathway used to control actions on-field may be different-and rely on different visual information-to the pathway often tested and trained off-field. However, the central claims of the TVSH are increasingly questioned, and this has implications for our understanding of vision and sport performance. The aim of this article is to outline the implications of the TVSH for the visual control of actions in sport. We first provide a summary of the TVSH and outline how the visual information used to control actions might differ from that usually tested. Second, we look at the evidence from studies of sports that are (and are not) consistent with the TVSH and the implications they have for training vision. Finally, we take a wider look at the impact of the TVSH on the sport sciences and other complementary theories that hold implications for training vision to improve sport performance.

Assessment of Visual Function and Performance in Paralympic Judo for Athletes with Vision Impairment.

SIGNIFICANCE: Paralympic judo currently requires all athletes to compete against each other in one class irrespective of their level of vision impairment (VI). Recent evidence suggests that multiple classes are required to enhance fairness, yet it remains unclear how many classes are necessary and what vision tests should be used to define those classes. PURPOSE: The aim of this study was to quantify the relationship between vision and performance in judo for individuals with VI. The results were expected to inform the development of evidence-based criteria to structure Paralympic judo competition. METHODS: The visual function of 53 elite VI judokas was assessed using a test battery that included tests of visual acuity (VA), contrast sensitivity, light sensitivity, depth perception, motion perception, visual search, and central visual field. Performance was assessed by measuring the ratio of fights won across all competitions the participants took part in in the 2 years before and after vision testing. Pearson correlation coefficients and decision tree analyses were used to determine the relationship between vision and performance. Partial correlations were also conducted to determine the unique ability of each measure of visual function to predict judo performance. RESULTS: Visual acuity was the best predictor of judo performance and remained the only visual function related to performance when controlling for correlations between VA and other visual functions. Decision tree analyses suggested to split athletes into two groups for more legitimate competition, using a cutoff point around 2.6 logMAR. Within each of the two resulting subgroups, no correlations remained between any of the visual functions and performance. CONCLUSIONS: The results of this study suggest that VI judo competition should be split into separate categories for partially sighted and functionally blind athletes. The inclusion of visual functions in addition to VA does not improve the ability to predict performance in VI judo.

Effect of vision impairment on match-related performance and technical variation in attacking moves in Paralympic judo.

In Paralympic judo for athletes with vision impairment (VI judo) all eligible athletes (i.e. B1, B2 and B3 classes) compete against each other in the same competition. Evidence suggests that athletes with more impairment may be disadvantaged, but that more sensitive measures of performance are necessary to understand the impact of impairment on performance. The aim of this study was to investigate the relationship between Para sport class and technical variation, time-motion variables, and performance in Paralympic judo. All 175 judo matches from the Rio 2016 Paralympic Games were analysed across 129 competitors (82 male and 47 female). The main results indicated that athletes who demonstrated less technical variation also experienced less competitive success, with the functionally blind athletes (class B1) demonstrating less technical variation than partially sighted (class B2 and B3) athletes (p < 0.05). There was no difference in the time-motion variables between sport classes (p > 0.05). We conclude that measures of technical variation are sensitive to differences in impairment and are suitable for studies that investigate the impairment-performance relationship in VI judo. Results further confirm that some athletes with impairment are disadvantaged under the current rules of VI judo.

May the best-sighted win? The relationship between visual function and performance in Para judo.

This study aimed to establish the optimal cut-off point(s) between classes in a new, evidence-based classification system for VI judo. We collected results from international VI judo competitions held between 2012 and 2018. Data on visual acuity (VA) and visual field (VF) measured during classification were obtained. Performance was determined by calculating a win ratio for each athlete. VA was significantly associated with judo performance (r = -.33, p <.001), VF was not (r =.30, p =.15). Decision tree analysis suggested to split the data into two groups with a VA cut-off of 2.5 logMAR units. Stability assessment using bootstrap sampling suggested a split into two groups, but showed considerable variability in the cut-off point between 2.0 and 3.5 logMAR. We conclude that to minimise the impact of impairment on the outcome of competition, VI judo should be split into two sport classes to separate partially sighted from functionally blind athletes. To establish an exact cut-off point and to decide if other measures of visual function need to be included, we argue for continued research efforts together with careful evaluation of research results from a multidisciplinary perspective.

Perspectives of a new sport-specific Para Shooting classification system for athletes with vision impairment.

The International Paralympic Committee (IPC) and individual sports federations have established the need to develop evidence-based systems of classification for athletes with vision impairment (VI) that may differ depending on the visual demands of each sport. As a consequence, research has been conducted that led to a new classification system for athletes competing in VI shooting. The purpose of this study was to canvas the experiences of key stakeholders (athletes, coaches and classifiers) when the new system of classification was implemented. Twenty-eight participants (17 athletes, 7 coaches and 4 classifiers) completed a questionnaire to rate their experiences of the previous and new classification systems and were interviewed to gain richer insights into their opinions. It was apparent that the changes to the classification system were not adequately communicated to the athletes in particular, and that the classifiers may require a better understanding of the principles of evidence-based classification. The new system was perceived to be significantly more specific for VI shooting and intentional misrepresentation was observed to be significantly less likely than when using the old system. This research provides valuable insights into both the positive and negative experiences of key stakeholders experiencing change in a classification system.

Expert opinion on classification for footballers with vision impairment: Towards evidence-based minimum impairment criteria.

In Para sport, the aim of classification is to minimize the impact of impairment on the outcome of competition. Despite requirements of the International Paralympic Committee Athlete Classification Code for classification to be evidence-based and sport-specific, sports for athletes with VI, including football, use the same generic classes across almost all sports. The aim of this study was to consult with experts to establish the needs and challenges for developing a code-compliant system of classification for VI football. A panel of 18 experts with international experience in VI football (16.8 ± 10.2 years) took part in a three-round Delphi study using online surveys. Results showed that the panel did not think that the current system completely fulfils the aim of classification. The panel identified measures of visual function they considered to be relevant but are not currently measured during classification including dynamic acuity, depth and motion perception, and contrast and light sensitivity. Moreover, they identified technical skills such as ball control, dribbling and passing, as well as perceptual-cognitive skills, as most likely to be affected by vision impairment. Findings outline the need for change and offer a framework for future research to develop an evidence-based classification for VI football.

Do visual fields need to be considered in classification criteria within visually impaired shooting?

Classification within the sport of vision impairment (VI) shooting is based upon the athlete's visual function. This study aimed to determine whether more than one class of competition is needed within VI shooting on the basis of visual field loss. Qualification scores of 23 elite athletes were obtained at World Championship events in prone and standing shooting disciplines. Visual field data were obtained from classification data and from assessment at events. A standardized scoring protocol determined whether athletes had function (≥10 dB) or no function (<10 dB) at locations between 0-60 degrees eccentricity along 10 meridia. Visual field function was not associated with shooting performance in prone or standing disciplines (p > 0.05). Having measurable visual field function beyond 30 degrees made no difference to athletes' ability to shoot competitively in prone (p = 0.65) or standing disciplines (p = 0.47), although a potential impact on qualification was observed in the standing discipline. There was no evidence that loss of visual field function at any specific location adversely affected ability to shoot competitively. There is currently no evidence to consider visual fields in classification within prone or standing VI shooting, although further research is needed as the sport grows.

Evidence-based Classification in Track Athletics for Athletes with a Vision Impairment: A Delphi Study.

SIGNIFICANCE: The Delphi analysis presented here highlights the need for a sport-specific evidence-based classification system for track athletics for athletes with a vision impairment (VI). This system may differ for different race distances. Further research is required to develop a useful test battery of vision tests for classification. The issue of intentional misrepresentation during classification needs particular attention. PURPOSE: At present, athletes with VI are placed into competition classes developed on the basis of legal definitions of VI. The International Paralympic Committee Athlete Classification Code states that all sports should have their own classification system designed to reflect the (visual) demands of that individual sport. This project gathered expert opinion on the specific requirements for an evidence-based sport-specific classification system for VI track athletics and to identify any particular issues within track athletics that require further research into their impact on sport performance. METHODS: A three-round Delphi review was conducted with a panel of 17 people with expertise in VI track athletics. RESULTS: The panel agreed that the current classification system in VI track athletics does not completely minimize the impact of impairment on competition outcome, highlighting the need for improvements. There was clear agreement that the existing measures of vision may fail to adequately reflect the type of vision loss that would impact running performance, with additional measures required. Intentional misrepresentation, where athletes "cheat" on classification tests, remains a serious concern. CONCLUSIONS: The panel has identified measures of vision and performance that will inform the development of an evidence-based classification system by better understanding the relationship between VI and performance in track athletics. Issues such as the use of guides and whether the current class system was equitable gave rise to differing opinions within the panel, with these varying across the different running distances.

Falling for a Fake: The Role of Kinematic and Non-kinematic Information in Deception Detection.

Kinematic and non-kinematic visual information have been examined in the context of movement anticipation by athletes, although less so in deception detection. This study examined the role of kinematic and non-kinematic visual information in the anticipation of deceptive and non-deceptive badminton shots. Skilled ( n = 12) and less skilled ( n = 12) badminton players anticipated the direction of deceptive and non-deceptive shots presented via video footage displayed in normal (kinematic and non-kinematic information), low (kinematic information emphasized), and high (non-kinematic information emphasized) spatial frequency conditions. Each shot was occluded one frame before shuttle-racquet contact or at contact. In deceptive trials, skilled players showed decreased anticipation accuracy in the high spatial frequency condition ( p = .050) compared to normal and low spatial frequency conditions, which did not differ. The study suggests that an emphasis on kinematic information results in accurate anticipation in response to deceptive movements and that an emphasis on non-kinematic information results in less accurate anticipation by experts.

Predictive eye movements when hitting a bouncing ball.

Predictive eye movements targeted toward the direction of ball bounce are a feature of gaze behavior when intercepting a target soon after it has bounced. However, there is conjecture over the exact location toward which these predictive eye movements are directed, and whether gaze during this period is moving or instead "lies in wait" for the ball to arrive. Therefore, the aim of this study was to further examine the location toward which predictive eye movements are made when hitting a bouncing ball. We tracked the eye and head movements of 23 novice participants who attempted to hit approaching tennis balls in a virtual environment. The balls differed in time from bounce to contact (300, 550, and 800 ms). Results revealed that participants made predictive saccades shortly before the ball bounced in two-thirds of all trials. These saccades were directed several degrees above the position at which the ball bounced, rather than toward the position at which it bounced or toward a position the ball would occupy shortly after the bounce. After the saccade, a separation of roles for the eyes and head ensured that gaze continued to change so that it was as close as possible to the ball soon after bounce. Smooth head movements were responsible for the immediate and ongoing changes in gaze to align it with the ball in the lateral direction, while eye movements realigned gaze with the ball in the vertical direction from approximately 100 ms after the ball changed its direction of motion after bounce. We conclude that predictive saccades direct gaze above the location at which the ball will bounce, presumably in order to facilitate ball tracking after the bounce.

The Effect of Vision Impairment on Competitive and Technical-Tactical Performance in Judo: Is the Present System Legitimate?

In judo competition for visual impairment, athletes of different classes compete against each other in the same category; B1 athletes are totally blind, whereas B2 and B3 athletes are partially sighted. To test for potential competition disparities due a single category of athletes, this study aimed to compare competitive and technical-tactical performance in visually impaired judo athletes with different degrees of visual impairment. The authors analyzed 340 judo matches from the 2012 and 2016 Paralympic Games. The scores, penalties, efficiency index, and types of medals were examined, as well as the technical variation and temporal structure. The main finding was that blind judo athletes presented lower scores (p < .05; effect size [ES] = 0.43-0.73), medals (p < .05), and efficiency (p < .05; ES = 0.40-0.73); different patterns of play; and a shorter time to lose than partially sighted athletes (p = .027; ES = 0.10-0.14). However, the penalties were similar between classes (p > .05; ES = 0.07-0.14). The odds ratio of a winning medal was 3.5-8 times less in blind athletes than in partially sighted athletes (p < .01). In conclusion, blind judo athletes presented lower competitive and technical-tactical performance than athletes with some residual functional vision. These findings provide support for the development of new evidence-based criteria for judo classification based on vision impairment.