The Role of Sports Vision in Eye Care Today

VisionCoach: Design and Effectiveness Study on VR Vision Training for Basketball Passing

Vision Training is important for basketball players to effectively search for teammates who has wide-open opportunities to shoot, observe the defenders around the wide-open teammates and quickly choose a proper way to pass the ball to the most suitable one. We develop an immersive virtual reality (VR) system called VisionCoach to simulate the player's viewing perspective and generate three designed systematic vision training tasks to benefit the cultivating procedure. By recording the player's eye gazing and dribbling video sequence, the proposed system can analyze the vision-related behavior to understand the training effectiveness. To demonstrate the proposed VR training system can facilitate the cultivation of vision ability, we recruited 14 experienced players to participate in a 6-week between-subject study, and conducted a study by comparing the most frequently used 2D vision training method called Vision Performance Enhancement (VPE) program with the proposed system. Qualitative experiences and quantitative training results are reported to show that the proposed immersive VR training system can effectively improve player's vision ability in terms of gaze behavior and dribbling stability. Furthermore, training in the VR-VisionCoach Condition can transfer the learned abilities to real scenario more easily than training in the 2D-VPE Condition.

Visual Performance and Sports: A Scoping Review

Vision is central to success in nearly all sports, and there is an emerging body of research investigating the links between visual abilities and athletic performance. This preregistered scoping review seeks to clarify the topics of study, methodologies used, populations under investigation, researchers, and disciplines driving this field. Systematic searches of English-language articles were conducted in PubMed and Web of Science, with additional literature identified through bibliographic searches. Six hundred sixty-seven articles published between 1976 and 2023 were identified with 547 empirical studies, 58 review articles, 20 commentaries, and 4 meta-analyses, among others. Among the empirical papers, 411 reported on visual assessments and 98 on vision training interventions. The most represented sports included baseball, soccer, basketball, and cricket, with over 150 articles reporting on professional, elite, or Olympic athletes. This scoping review describes the breadth of this emerging field, identifies its strengths and weaknesses, and provides recommendations for future improvement.

Vertical dynamic visual acuity is significantly lower than horizontal dynamic visual acuity

Dynamic visual acuity (DVA) is crucial for the perception of moving objects. While traditional DVA assessment tools predominantly focus on horizontal movements, the evaluation of vertical DVA remains unstandardized. Consequently, the disparities between vertical and horizontal DVAs are yet to be thoroughly investigated. Therefore, we designed a system capable of conducting multidirectional DVA tests and eye movement measurements. During the experiments, the participants identified the gap direction of the Landolt-C ring moving either horizontally or vertically. The speed of movement decelerated from its maximum as a high-speed infrared camera captured the pupil movements of the left eye at 500 fps. We conducted tests on 15 healthy university students (aged [Formula: see text] years) and measured vertical and horizontal DVAs five times each. DVA was deduced from the Landolt-C ring speed with accurate gap direction responses, and eye movement was assessed based on the total gaze movement distance. The results revealed superior DVA and eye movement in the horizontal direction compared with the vertical direction ([Formula: see text]). This highlights the anisotropic characteristics of DVA and eye movement. The proposed system has the potential for multidirectional dynamic vision evaluation and training in clinical scenarios.

Sunglass tint does not impact the indoor catching performance of cricket fielders

Introduction

Sunglasses are worn by outdoor athletes such as cricketers for many reasons, including comfort and glare reduction, which may help to improve vision. Anecdotally they are purported to have performance-enhancing benefits, but there is a lack of evidence for this. Further, it appears that fielders are the only position in cricket who wear sunglasses. Therefore, this study aimed to compare the catching performance of fielders when wearing three different colour sunglasses tints during an indoor, laboratory-based experiment.

Methods

Twenty-one male cricketers currently playing for a university or amateur provincial teams in Makhanda, South Africa, who were non-habitual sunglass wearers, were recruited for this study. An optometrist administered pre-screening tests. Players had four testing sessions during which they wore a different colour tint at each session indoors (clear, blue, G30 (rose), and red). Players were required to catch 18 balls projected from a bowling machine. The number of balls caught, as well as the quality of the catch, was recorded. At the final session, they were asked which tint they thought was best.

Results

Pre-screening tests showed that the red lens was best for contrast sensitivity and stereopsis. During data collection, sunglass tint did not affect catching performance. The players perceived the red lens as the worst and the G30 as the best.

Discussion

It can be concluded that catching performance indoors is not affected by tint colour.

Studies of Vision in Cricket-A Narrative Review

Vision is thought to play a substantial role in hitting and fielding in cricket. An understanding of which visual skills contribute during cricket play could inform future clinical training trials. This paper reviews what has been reported thus far regarding the relationship of visual skills to cricket performance and reviews the results of clinical trials in which the impact of visual skills training on cricket performance has been addressed. Fundamental or low-level visual skills, with the exception of color vision and perhaps near stereopsis and dynamic visual acuity, are similar between cricket players and the general population. Simple reaction time has been found to be shorter in cricket players in some but not all studies. While there is mixed or no evidence that the aforementioned visual skills are superior in cricket players compared to non-players, comparisons of eye and head movements and gaze tracking have revealed consistent differences between elite cricket batters and sub-elite batters. Future training studies could examine whether teaching sub-elite batters to emulate the gaze tracking patterns of elite batters is beneficial for batting. Lastly, clinical trials in which visual skills of cricket players have been trained have in many cases resulted in positive effects on visual skills, or judgments required in cricket, or cricket play. However, clinical trials with larger and more diverse groups of participants and correlations to on-field metrics and on-field performance (i.e., domain-specific assessments) are necessary before conclusions can be drawn regarding the efficacy of vision training.

A review of the essential visual skills required for soccer: Beyond 20-20 optometry

In ball sports such as soccer, the visual system is critical in guiding a player's search for crucial information that underpins skillful behavior, which requires the incorporation of all of the relevant information in the environment in order to make successful decisions under pressure. However, vision in sport, and focusing on the specific visual skills required to be successful in a particular sport has largely been a practice ignored by experts and coaches as being an essential component of athletic performance. This is the first attempt to summarize and compile the necessary visual skills for soccer. This review's evidence suggests that, while current research still tends to focus on visual skills as a whole, there is a need to streamline this focus to the necessities of a particular sport. Furthermore, in identifying the visual skills essential for soccer, it allows for the effective training and testing of these skills, as well as for talent identification.

Athletes Demonstrate Superior Dynamic Visual Acuity

SIGNIFICANCE

Athletes exhibit better dynamic visual acuity (DVA) compared with nonathletes, whereas action video game players (VGPs) perform more similarly to controls despite having similar static visual acuity and refractive errors. The differences in DVA between groups were not related to differences in static visual acuity, refractive error, or smooth pursuit gain.

PURPOSE

The purpose of the study was to examine whether athletes and VGPs have superior DVA than controls (nonathletes, nongamers).

METHODS

Forty-six participants (15 athletes, 11 VGPs, 20 controls) aged 21.7 years (standard deviation, 2.8 years) were recruited. Participants were emmetropic with equivalent monocular and binocular static visual acuity between groups. Dynamic visual acuity was assessed using predictable (horizontal) and unpredictable (random) motion targets at velocities of 5, 10, 20, and 30°/s. Smooth pursuit eye movements were assessed using a horizontal motion step-ramp stimulus at the same speeds. This study was pre-registered with the Center for Open Science (https://osf.io/eu7qc).

RESULTS

At 30°/s, there were significant main effects of group (F = 4.762, P = .01) and motion type (F = 9.538, P = .004). Tukey post hoc analysis for groups indicated that athletes performed better than did the control group (t = -2.919, P < .02). An omnibus (group × motion type × speed) repeated measures ANOVA showed a main effect of speed (F = 110.137, P < .001) and a speed × motion-type interaction (F = 27.825, P < .001). Dynamic visual acuity decreased as speed increased, and the slope of the change was greater for random than for horizontal motion. Smooth pursuit gains were not significantly different between groups (P > .05).

CONCLUSIONS

Athletes have superior dynamic visual acuity performance compared with controls at 30°/s. This between-group difference cannot be fully explained by differences in smooth pursuit eye movements and therefore may reflect other differences between the groups.

Association between Clinical Vision Measures and Visual Perception and Soccer Referees' On-field Performance

SIGNIFICANCE

The decisions taken by soccer officials are critically important to game management. Understanding the underlying processes that mediate expert performance in soccer refereeing may lead to a better standard of officiating. Vision is the dominant source of incoming information upon which officials rely to make their on-field decisions.

PURPOSE

We tested the hypothesis that performance on generic tests of vision and visual perception predicts domain-specific performance in elite-level soccer referees (R) and assistant referees (AR).

METHODS

We assessed the vision of R and AR who officiate at the highest level in Portugal. To be eligible for inclusion, R and AR had to have officiated for at least two consecutive seasons across the 2014/2015, 2015/2016, and 2016/2017 seasons. A single, rank-order list of the performance of eligible officials was created based on the rank-order list for each season that was made by the Portuguese Soccer Federation. Clinical vision measures included visual acuity and stereoacuity, and visual perception measures were gathered using the Test of Visual Perceptual Skills, Third Edition.

RESULTS

A total of 59 officials participated (21 R, 38 AR), 17 of whom officiated at the international level. The R and AR groups did not differ in vision or visual perception measures. We found that better stereoacuity (P < .001) and visual memory (P = .001) are associated with a higher rank order of on-field performance after adjusting for the age, experience, the national/international status, and the regional affiliation of the officials. Together, these two measures explain 22% of the variance in rank-order performance.

CONCLUSIONS

This is the first study to show a link between the vision of officials and their on-field performance. The origin and significance of these findings remain to be established, and further work is required to establish whether they are component skills in the domain of soccer refereeing.

Topical Review: Perceptual-cognitive Skills, Methods, and Skill-based Comparisons in Interceptive Sports

SIGNIFICANCE

We give a comprehensive picture of perceptual-cognitive (PC) skills that could contribute to performance in interceptive sports. Both visual skills that are low level and unlikely influenced by experience and higher-level cognitive-attentional skills are considered, informing practitioners for identification and training and alerting researchers to gaps in the literature.Perceptual-cognitive skills and abilities are keys to success in interceptive sports. The interest in identifying which skills and abilities underpin success and hence should be selected and developed is likely going to grow as technologies for skill testing and training continue to advance. Many different methods and measures have been applied to the study of PC skills in the research laboratory and in the field, and research findings across studies have often been inconsistent. In this article, we provide definitional clarity regarding whether a skill is primarily visual attentional (ranging from fundamental/low-level skills to high-level skills) or cognitive. We review those skills that have been studied using sport-specific stimuli or tests, such as postural cue anticipation in baseball, as well as those that are mostly devoid of sport context, considered general skills, such as dynamic visual acuity. In addition to detailing the PC skills and associated methods, we provide an accompanying table of published research since 1995, highlighting studies (for various skills and sports) that have and have not differentiated across skill groups.

Review: The Quiet Eye in Sports Performance-Is the Quiet Eye the Ultimate Explanation or Only the Beginning?

SIGNIFICANCE

The quiet eye is a gaze behavior that seems to differentiate both expert-novice performance and successful and unsuccessful performance in experts; however, the quiet eye may only represent one aspect of the perceptual-cognitive expertise differences that exist between athletes and nonathletes.Research suggests that expert-novice differences in vision and visual-motor coordination skills exist between athletes and nonathletes, although the underlying mechanisms driving these differences are not well understood. The quiet eye is the final fixation or tracking gaze made before the initiation of the action of importance in a motor coordination task and is quite possibly the most well-studied vision strategy variable in sport. The quiet eye has been shown to be a key component of both expert ability and successful performance. However, the quiet eye is not without its criticisms, and the perceptual mechanisms underlying this unique gaze behavior are not yet well understood. The question that remains to be answered is whether the differences in vision and visual-motor coordination skills that exist between athletes and nonathletes can be explained by the quiet eye alone or if the explanation is more complicated.

Citations Network Analysis of Vision and Sport

Background: Sports vision is a relatively new specialty, which has attracted particular interest in recent years from trainers and athletes, who are looking at ways of improving their visual skills to attain better performance on the field of play. The objective of this study was to use citation networks to analyze the relationships between the different publications and authors, as well as to identify the different areas of research and determine the most cited publication. Methods: The search for publications was carried out in the Web of Science database, using the terms "sport", "vision", and "eye" for the period between 1911 and August 2020. The publication analysis was performed using the Citation Network Explorer and CiteSpace software. Results: In total, 635 publications and 801 citations were found across the network, with 2019 being the year with the highest number of publications. The most cited publication was published in 2002 by Williams et al. By using the clustering functionality, four groups covering the different research areas in this field were found: ocular lesion, visual training methods and efficiency, visual fixation training, and concussions. Conclusions: The citation network offers an objective and comprehensive analysis of the main papers on sports vision.

Static and dynamic visual acuity and refractive errors in elite football players

BACKGROUND

The aim of this study was to investigate static and dynamic visual acuity, refractive error, and the use of visual compensation of elite football players.

METHODS

From 2015 to 2017, 147 professional players from five teams were analysed. Screening consisted of a survey about the use of visual correction, and measurement refractive error, static visual acuity and dynamic visual acuity. Refractive error was assessed using an autorefractor. Distance static visual acuity was evaluated using a Snellen chart. Dynamic visual acuity was measured at five metres using the software COI-SV. All athletes were male with a mean age of 24.6 ± 4.1 years.

RESULTS

The mean refractive error of the athletes was -0.04 ± 0.83 D, and 16.4 per cent were myopic. Statistically significant differences were found for dynamic visual acuity (p = 0.033), based on the position occupied. Goalkeepers displayed the best dynamic visual acuity and forwards had the lowest values (0.82 ± 0.14 and 0.62 ± 0.17, respectively). The forwards presented with the highest prevalence of myopia and goalkeepers the lowest, at 22.5 per cent and 12.5 per cent, respectively. All goalkeepers who needed to use a correction for play used it, whereas only 16 per cent of the forwards who needed a correction used it.

CONCLUSION

Dynamic visual acuity of forwards is lower than that of other players. Twenty-five per cent of players who need to use visual correction to practice sports actually use it.

Modified perceptual training in sport: A new classification framework

OBJECTIVES

To overview a framework that provides a theoretically-grounded approach to predicting the types of modified perceptual training tasks that will stimulate transfer of improved perceptual skills to sport performance environments. Modified perceptual training (MPT) collectively describes on- or off-field sports training tasks that are specifically designed to develop visual and perceptual-cognitive skill. Traditional training approaches in sport include sports vision training and perceptual-cognitive training, while recently, new technologies have enabled a broad range of additional MPT tools to become available to coaches and athletes.

DESIGN

Short literature review and opinion article.

METHODS

Literature in the fields of sports vision training and perceptual-cognitive training are summarised and contrasted. A selection of emerging MPT technologies are then overviewed. This leads to the identification of three interacting factors of MPT task design that may influence the task's capacity to transfer improved training performance to actual competition: (i) the targeted perceptual function, (ii) stimulus correspondence, and (iii) response correspondence, which are assimilated with key tenets of representative learning design.

RESULTS

These three theoretically-grounded differences are adopted to support and justify the structure of the Modified Perceptual Training Framework which sets out predictions for future research to test in order to clarify the transfer effect of MPT tools.

CONCLUSIONS

The application of the Modified Perceptual Training Framework may assist in future testing, design and selection of beneficial training tools in sport and as such, is predicted to have significant impact in empirical and practical settings.

Vision in high-level football officials

Officiating in football depends, at least to some extent, upon adequate visual function. However, there is no vision standard for football officiating and the nature of the relationship between officiating performance and level of vision is unknown. As a first step in characterising this relationship, we report on the clinically-measured vision and on the perceived level of vision in elite-level, Portuguese football officials. Seventy-one referees (R) and assistant referees (AR) participated in the study, representing 92% of the total population of elite level football officials in Portugal in the 2013/2014 season. Nine of the 22 Rs (40.9%) and ten of the 49 ARs (20.4%) were international-level. Information about visual history was also gathered. Perceived vision was assessed using the preference-values-assigned-to-global-visual-status (PVVS) and the Quality-of-Vision (QoV) questionnaire. Standard clinical vision measures (including visual acuity, contrast sensitivity and stereopsis) were gathered in a subset (n = 44, 62%) of the participants. Data were analysed according to the type (R/AR) and level (international/national) of official, and Bonferroni corrections were applied to reduce the risk of type I errors. Adopting criterion for statistical significance of p<0.01, PVVS scores did not differ between R and AR (p = 0.88), or between national- and international-level officials (p = 0.66). Similarly, QoV scores did not differ between R and AR in frequency (p = 0.50), severity (p = 0.71) or bothersomeness (p = 0.81) of symptoms, or between international-level vs national-level officials for frequency (p = 0.03) or bothersomeness (p = 0.07) of symptoms. However, international-level officials reported less severe symptoms than their national-level counterparts (p<0.01). Overall, 18.3% of officials had either never had an eye examination or if they had, it was more than 3 years previously. Regarding refractive correction, 4.2% had undergone refractive surgery and 23.9% wear contact lenses when officiating. Clinical vision measures in the football officials were similar to published normative values for young, adult populations and similar between R and AR. Clinically-measured vision did not differ according to officiating level. Visual acuity measured with and without a pinhole disc indicated that around one quarter of participants may be capable of better vision when officiating, as evidenced by better acuity (≥1 line of letters) using the pinhole. Amongst the clinical visual tests we used, we did not find evidence for above-average performance in elite-level football officials. Although the impact of uncorrected mild to moderate refractive error upon officiating performance is unknown, with a greater uptake of eye examinations, visual acuity may be improved in around a quarter of officials.

Contributions of Visuo-oculomotor Abilities to Interceptive Skills in Sports

PURPOSE

Monitoring and intercepting a fast approaching object is a critical skill for many sports. Athletes might be distinguished from nonathletes based on their ability to access various visual abilities to accomplish interceptive actions. Here, we examined whether interceptive visuomotor skills of athletes and nonathletes are differently correlated to a hierarchy of visuo-oculomotor abilities related to the perception of motion in depth.

METHODS

Eighty-six athletes in interceptive sports, as well as 60 nonathletes, were recruited based on their sport performance and prior experiences. Their basic visual abilities (dominant eye acuity, contrast sensitivity, visual span, and visual memory) and complex visuo-oculomotor abilities (dynamic acuity, accommodative facility, near point of convergence, and near/far phoria) were analyzed in relation to critical visuomotor skills (manual interception, visually guided locomotion, and depth judgment).

RESULTS

Discriminant analysis revealed that athletes and nonathletes can be accurately differentiated based on measured visuomotor skills (91.3% accuracy, p < 0.0001). Near point of convergence, accommodative facility, and dynamic acuity were moderately effective in identifying athletes (71.3%, p = 0.002) and in predicting the three visuomotor skills (all r(2) ≥ 0.096, all p ≤ 0.022). Dominant eye acuity and contrast sensitivity also identified athletes (61.4%, p = 0.021) and contributed to complex visuo-oculomotor abilities (all r(2) ≥ 0.046, all p ≤ 0.039). The correlations among measured abilities were more significant for athletes than nonathletes.

CONCLUSIONS

Athletes in interceptive sports are superior to nonathletes in their visuomotor skills. They also have broader access to various visual and complex visuo-oculomotor abilities than nonathletes. This likely allows athletes to more effectively coordinate visual and oculomotor abilities under demanding conditions when some visual cues are degraded. The present findings are consistent with a pyramid of sports vision and suggest a top-down process for athlete screening and training.