RESUMO
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.
Assuntos
Críquete , Tomada de Decisões , Julgamento , Humanos , Críquete/fisiologia , Masculino , Feminino , Adulto , Adulto Jovem , Perna (Membro)/fisiologiaRESUMO
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.
Assuntos
Corrida , Humanos , Corrida/fisiologia , Adulto , Masculino , Feminino , Adulto Jovem , Fixação Ocular/fisiologiaRESUMO
OBJECTIVES: Investigate the visibility of new and old red, white and pink cricket balls under lighting and background conditions experienced during a day-night cricket match. DESIGN: We modelled the luminance contrast signals available for a typical observer for a ball against backgrounds in a professional cricket ground, at different times of day. METHODS: Spectral reflectance (light reflected as a function of wavelength) was derived from laboratory measurements of new and old red, white and pink balls. We also gathered spectral measurements from backgrounds (pitch, grass, sightscreens, crowd, sky) and spectral illuminance during a day-night match (natural afternoon light, through dusk to night under floodlights) from Lord's Cricket Ground (London, UK). The luminance contrast of the ball relative to the background was calculated for each combination of ball, time of day, and background surface. RESULTS: Old red and old pink balls may offer little or no contrast against the grass, pitch and crowd. New pink balls can also be of low contrast against the crowd at dusk, as can pink and white balls (of any age) against the sky at dusk. CONCLUSIONS: Reports of difficulties with visibility of the pink ball are supported by our data. However, our modelling also shows that difficulties with visibility may also be expected under certain circumstances for red and white balls. The variable conditions in a cricket ground and the changing colour of an ageing ball make maintaining good visibility of the ball a challenge when playing day-night matches.
Assuntos
Críquete , Humanos , Críquete/fisiologia , Equipamentos Esportivos , Iluminação , Sensibilidades de Contraste/fisiologiaRESUMO
OBJECTIVE: This study aimed to explore the profile of athletes with a vision impairment who compete in three Paralympic sports (goalball, vision impairment judo, and blind football). DESIGN: Descriptive and association analyses of the vision impairment athletes' profile were conducted. RESULTS: The typical athlete profile was a male (65.1%), aged 26-34 yrs (39.7%), from Europe (38.8%), representing a country with a high income (46.1%), and was diagnosed with a retinal-related ocular pathology (38.9%). In all three sports, the ages of the athletes were similar. In goalball, most athletes were from Europe, represented countries with a high income, and were diagnosed with retinal-, globe-, or neurological-related pathologies. In vision impairment judo, the majority of athletes were from Asia, represented countries with an upper middle income, and were diagnosed with retinal-, global-, or neurological-related pathologies. In blind football, most athletes were from Europe, represented countries with an upper middle income, and were diagnosed with retinal-, neurological-related ocular pathologies, or glaucoma. CONCLUSIONS: The homogeneity of the athletes' profile suggests that an effort is needed to target other parts of the vision impairment population to take part in vision impairment sports. Differences in the athletes' profiles across the sports provide information that may be useful for sport-specific talent identification.
Assuntos
Futebol Americano , Artes Marciais , Humanos , Masculino , Atletas , DemografiaRESUMO
OBJECTIVE: This study aimed to investigate the difference of running with or without a guide on running performance (100, 200, and 400 m) for athletes with a vision impairment. DESIGN: Data including athletes' and guides' sex, age, and race times were extracted from 11 elite competitions. RESULTS: Male athletes predominantly ran without a guide (100 m = 91.4%, 200 m = 88.1%, 400 m = 84.8%), whereas female athletes mainly ran with a guide (100 m = 60.5%, 200 m = 80.0%, 400 m = 72.0%). No significant difference in 100-m race times was found between male athletes with or without a guide ( P = 0.647). For the 200 m ( P = 0.001) and 400 m ( P = 0.030), race times were significantly slower for male athletes running with a guide (mean rank 200 m = 36.80, 400 m = 33.57) compared to without a guide (mean rank 200 m = 19.43, 400 m = 21.69). Conversely, 100- ( P = 0.015), 200- ( P = 0.025), and 400-m ( P = 0.029) race times were significantly faster for female athletes with (mean rank 100 m = 18.25, 200 m = 13.71, 400 m = 11.00) compared with without a guide (mean rank 100 m = 27.74, 200 m = 22.67, 400 m = 21.69). CONCLUSIONS: Running with a guide affects vision impairment athletes' race times. The influence of running with a guide, and the gender mix of vision impairment athlete and guide, should be considered in any research with the aim of establishing a new classification system for vision impairment athletes.
Assuntos
Desempenho Atlético , Corrida , Humanos , Masculino , Feminino , AtletasRESUMO
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.
Assuntos
Paratletas , Futebol , Transtornos da Visão , Humanos , Desempenho AtléticoRESUMO
Decision making is vital in complex sporting tasks but is difficult to test and train. New technologies such as virtual and augmented reality offer novel opportunities for improving decision making, yet it remains unclear whether training gains using these new approaches will improve decision making on-field. To clarify the potential benefits, a clear conceptualization of decision making is required, particularly for invasive team sports such as football, basketball and field hockey, where decisions are complex with many possible options offered. Therefore, the aim of this position paper is to establish a framework for the design of virtual and augmented environments that help invasive team sport athletes to train their decision-making capacities. To achieve this, we propose a framework for conceptualising 'natural' decision making within the performance environment in invasive team sports that views decision making as a continuous cyclical process where the ball carrier interacts with teammates to create 'windows of opportunity', and where skilled decision makers often delay decisions to create time, and in turn new opportunities, rather than necessarily selecting the first option available to them. Within the framework, we make a distinction between decision making and anticipation, proposing that decision making requires a series of on-going anticipatory judgments. Based on the framework, we subsequently highlight the consequences for testing and training decision making using virtual and augmented reality environments, in particular outlining the technological challenges that need to be overcome for natural decision making to be represented within virtual and augmented environments.
Assuntos
Basquetebol , Futebol Americano , Humanos , Esportes de Equipe , Tomada de DecisõesRESUMO
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.
Assuntos
Hóquei , Humanos , Hóquei/fisiologia , Estudos Retrospectivos , AptidãoRESUMO
Visual experience plays an important role in facilitating referee decision-making. Video training can be used to train these perceptual-cognitive skills in discrete scenarios, for instance in foul situations in football, but is less suitable in other instances such as when seeking to make decisions in open-play scenarios due to a lack of representativeness. Recent technological advances enable the use of virtual reality (VR) to replicate game situations in a controlled and realistic manner. It is however not yet known how representative behaviour in VR would be of behaviour on-field in the natural environment. The aim of the study was therefore to examine the degree to which visual behaviour of football referees in virtual reality would reflect behaviour found when adjudicating matches on-field. Sub-elite football referees completed decision-making tasks in three experimental conditions: on-field (in a real match), in virtual reality and when observing video footage. Across the three environments we compared decision-making performance, visual behaviour (including search rate, fixation duration, and head movements) and the user experience of the referees. Results revealed that behaviour in the VR environment was indistinguishable from that on-field. In contrast, visual-motor behaviour when observing video footage was markedly different to that found on-field (and in VR). The results show that visual-motor behaviour in VR is representative of that found on-field and therefore suggests that VR offers promise as a representative training environment for sports officials to improve on-field performance in the natural environment.
Assuntos
Futebol Americano , Realidade Virtual , Humanos , Tomada de DecisõesRESUMO
Skilled actors rely on deception to disrupt the perceptual ability of opponents who seek to anticipate action intentions. Common-coding theory (Prinz, 1997) purports that action and perception share common origins in the brain, and therefore it seems plausible that the ability to 'see through' a deceptive action would be associated with a capacity to perform the same action. The aim of this study was to investigate whether the ability to perform a deceptive action would be related to the ability to perceive the same type of action. Fourteen skilled rugby players performed deceptive (side-step) and non-deceptive actions while running towards a camera. The deceptiveness of those participants was determined by testing the ability of a separate group of eight equally skilled observers to anticipate the impeding running directions using a temporally occluded video-based test. Based on the overall response accuracies, participants were separated into high- and low-deceptiveness groups. These two groups then themselves took part in a video-based test. Results revealed that the skilled deceivers had a significant advantage in their ability to better anticipate the action outcomes of highly deceptive actions. The skilled deceivers' sensitivity to discriminate deceptive from non-deceptive actions was significantly better than that of less-skilled deceivers when viewing the most-deceptive actor. Moreover, the skilled perceivers performed actions that appeared to be better disguised than those of the less-skilled perceivers. These findings suggest that, consistent with common-coding theory, the perception of deceptive and non-deceptive actions is associated with the capability to produce deceptive actions and vice versa.
Assuntos
Percepção de Movimento , Corrida , Humanos , Percepção de Movimento/fisiologia , Encéfalo , EnganaçãoRESUMO
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.
Assuntos
Pessoas com Deficiência , Esportes para Pessoas com Deficiência , Humanos , Técnica Delphi , Pessoas com Deficiência/classificação , Avaliação da Deficiência , Masculino , Feminino , Transtornos da Visão/classificaçãoRESUMO
OBJECTIVES: This study aimed to identify facilitators and barriers to participation in vision impaired golf. DESIGN: Semistructured interviews were conducted with 12 vision impaired golfers, 10 guides, and 5 novices during the British VI Golf Open tournament in August 2021. RESULTS: Qualitative content analysis identified the benefits, facilitators, and challenges of playing vision impaired golf. The role of guides and future developments of the sport were furthermore identified. The benefits extend beyond those related to health, including personal development and a sense of purpose for players and of reward for guides. Facilitators were largely organizational and having appropriate support and a guide. The challenges to playing and guiding were practical, financial, and logistical. The need to attract a more diverse range of players, along with a reconsideration of the eligibility criteria, was central to the perceived sustainability of vision impaired golf. CONCLUSIONS: These results highlight the practical, financial, and logistical challenges contributing to vision impaired golf activity limitations and participation restrictions. Because of the health, personal, and psychosocial benefits, ways of providing practical, financial, and support networks to facilitate engagement in vision impaired golf should be sought. An evidence-based, sport-specific eligibility system was thought to be critical for the future promotion of vision impaired golf.
Assuntos
Golfe , Esportes , Humanos , Pesquisa Qualitativa , Inquéritos e QuestionáriosRESUMO
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.
Assuntos
Desempenho Psicomotor , Movimentos Sacádicos , Humanos , Desempenho Psicomotor/fisiologia , Movimentos Oculares , Acompanhamento Ocular Uniforme , Percepção VisualRESUMO
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.
Assuntos
Tecnologia de Rastreamento Ocular , Nistagmo Patológico , Humanos , Retina , Acompanhamento Ocular UniformeRESUMO
In order to intercept a moving target such as a baseball with high spatio-temporal accuracy, the perception of the target's movement speed is important for estimating when and where the target will arrive. However, it is unclear what sources of information are used by a batter to estimate ball speed and how those sources of information are integrated to facilitate successful interception. In this study, we examined the degree to which kinematic and ball-flight information are integrated when estimating ball speed in baseball batting. Thirteen university level baseball batters performed a ball-speed evaluation task in a virtual environment where they were required to determine which of two comparison baseball pitches (i.e., a reference and comparison stimuli) they perceived to be faster. The reference and comparison stimuli had the same physical ball speed, but with different pitching movement speeds in the comparison stimuli. The task was performed under slow (125 km/h) and fast (145 km/h) ball-speed conditions. Results revealed that the perceived ball-speed was influenced by the movement speed of the pitcher's motion, with the influence of the pitcher's motion more pronounced in the fast ball-speed condition when ball-flight information was presumably less reliable. Moreover, exploratory analyses suggested that the more skilled batters were increasingly likely to integrate the two sources of information according to their relative reliability when making judgements of ball speed. The results provide important insights into how skilled performers may make judgements of speed and time to contact, and further enhance our understanding of how the ability to make those judgements might improve when developing expertise in hitting.
RESUMO
OBJECTIVES: This study aimed to determine whether elite cricket umpires' decisions contribute to home advantage via leg-before-wicket decisions. DESIGN: Leg-before-wicket decisions (nâ¯=â¯4971) from actual elite level cricket matches in Australia between 2009 and 2016 were analysed using a binomial logistic regression to predict the umpires' leg-before-wicket decisions. METHODS: Regressions were performed to determine whether the batter's team (home or away) influenced the likelihood that the umpire would give them out leg-before-wicket. RESULTS: We found no evidence of home advantage in umpires' leg-before-wicket decisions. In fact, we found evidence that umpires in some instances disadvantage the home team. CONCLUSIONS: We suggest that the increased professionalism of sports officials, and the scrutiny they are placed under, may lead umpires to reduce or even overcompensate for any existing biases in their decision making.
Assuntos
Tomada de Decisões , Austrália , HumanosRESUMO
BACKGROUND: Paralympic swimmers with vision impairment (VI) currently compete in one of the three classes depending on their visual acuity (VA) and/or visual field. However, there is no evidence to suggest that a three-class system is the most legitimate approach for classification in swimming, or that the tests of VA and visual field are the most suitable. An evidence-based approach is required to establish the relationship between visual function and performance in the sport. Therefore, the aim of this study was to establish the relationship between visual function and performance in VI Para swimming. The swimming performance of 45 elite VI swimmers was evaluated during international competitions by measuring the total race time, start time, clean swim velocity, ability to swim in a straight line, turn time, and finish time. Visual function was measured using a test battery that included VA, contrast sensitivity, light sensitivity, depth perception, visual search, and motion perception. RESULTS: Results revealed that VA was the best predictor of total race time (r = 0.40, p < 0.01), though the relationship was not linear. Decision tree analysis suggested that only two classes were necessary for legitimate competition in VI swimming, with a single cut-off between 2.6 and 3.5 logMAR. No further significant association remained between visual function and performance in either of the two resulting classes (all |rs|< 0.11 and ps > 0.54). CONCLUSIONS: Results suggest that legitimate competition in VI swimming requires one class for partially sighted and another for functionally blind athletes.
RESUMO
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.
Assuntos
Desempenho Atlético , Futebol , Adolescente , Criança , Humanos , Masculino , Aptidão , Estudos Transversais , Estudos LongitudinaisRESUMO
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.