Exercise Dependency and Overuse Injuries in Attention Deficit Hyperactivity Disorder.

ABSTRACT: Attention deficit hyperactivity disorder (ADHD) is a common condition, but current medications have limitations, pushing a drive for alternative approaches. Different exercise-focused approaches have shown promise, but concern has also been raised about individuals with ADHD showing greater risk of addiction, including exercise dependency. Using an online survey, we examined current exercise practices, including exercise dependency and the presence of overuse injury, which could result from overexercising, in 114 adults with ADHD. We found that most were regularly exercising. None were classified as exercise dependent, but 38.9% were deemed symptomatic nondependent. Hyperactive-impulsive symptoms were a predictor of the level of exercise withdrawal experienced, and the co-occurrence of autism spectrum disorder was associated with greater risk of overuse injuries. The data indicate that ADHD may confer some greater risk of exercise dependency, aligning with previous studies investigating other addictions and suggesting further research is critical.

Examining the importance of local and global patterns for familiarity detection in soccer action sequences.

Pattern recognition is a defining characteristic of expertise across multiple domains. Given the dynamic interactions at local and global levels, team sports can provide a vehicle for investigating skilled pattern recognition. The aims of this study were to investigate whether global patterns could be recognised on the basis of localised relational information and if relations between certain display features were more important than others for successful pattern recognition. Elite (n = 20), skilled (n = 34) and less-skilled (n = 37) soccer players completed three recognition paradigms of stimuli presented in point-light format across three counterbalanced conditions: 'whole-part'; 'part-whole'; and 'whole-whole'. 'Whole' clips represented a 11 vs. 11 soccer match and 'part' clips presented the same passages of play with only two central attacking players or two peripheral players shown. Elite players recognised significantly more accurately than the skilled and less-skilled groups. Participants were significantly more accurate in the 'whole-whole' condition compared to others, and recognised stimuli featuring the two central attacking players significantly more accurately than those featuring peripheral players. Findings provide evidence that elite players can encode localised relations and then extrapolate this information to recognise more global macro patterns.

The effects of internal representations on performance and fluidity in a motor task.

Individuals can differ in the mode in which they experience conscious thought. These differences in visualisation and verbalisation can also be evident during motor control. The Internal Representation Questionnaire (IRQ) was developed to measure propensity to engage certain types of representations, but its ability to predict motor control and links to reinvestment and motor imagery have not been tested. 159 included participants completed the IRQ, movement specific reinvestment scale (MSRS), and a novel online motor task before and after a period of practice. Results showed that the IRQ Verbal and Orthographic factors were significant predictors of scores on the MSRS. The IRQ factor of Manipulational Representations predicted motor performance both before and after practice. The fluidity of executed movements were predicted by the IRQ verbalisation factor where higher propensity to verbalise was associated with higher levels of jitter, but only after a period of practice. Results suggest there may be some informative conceptual overlap between internal verbalisations and reinvestment and that the propensity to manipulate internal representations may be predictive of motor performance in new tasks. The IRQ has potential to be a valuable tool for predicting motor performance.

The developmental activities of women's professional pathway cricketers.

The growth of investment in women's cricket has led to the development of new professional pathways. However, there is lack of specific evidence to support the development of these athletes. This study aimed to take a first step in understanding the participation histories of female cricketers selected into English women's professional academies. 84 players completed the Participation History Questionnaire (PHQ) to capture details of activities engaged in across development, including milestones, cricket activity, and engagement in other sport activities. There were relative age effects where players' birthdate distributions differed from national norms (X2 = 8.451, p = .003, V = 0.227), and more players than expected attended independent schools (X2 = 7.980, p = .005, V = 0.232). Participants engaged in cricket informally before coach led training, have siblings (particularly brothers) interested in cricket and often played boy's cricket before engaging in the girl's or women's game. Developmental activities were characterised by early engagement, high levels of diversification, and very low levels of play compared to high levels of formal practice and match play. These findings have implications for the advancement of talent identification and development policies and processes in women's cricket.

"I Found Comfort in Exercising": Exploring Experiences With Exercise for Adults With Attention-Deficit/Hyperactivity Disorder.

Little is known about how adults with attention-deficit/hyperactivity disorder (ADHD) experience exercise, resulting in a lack of recommendations for supporting this population. We aimed to explore how adults with ADHD experience exercise as a management tool before and after diagnosis and how and why individuals experience issues related to exercise dependence. Fifteen active adults with a diagnosis of ADHD participated in semistructured interviews. Three overarching themes were identified: (a) exercise as a necessity for ADHD, reflecting the need to exercise before a formal ADHD diagnosis, and use of exercise as a management tool postdiagnosis; (b) goals and achievements to live by, reflecting how exercise patterns revolved around a need to make progress toward targets; and (c) activity or exercise: a roller coaster journey, covering the ups and downs of exercise journeys. This article highlights the importance of exercise for adults to manage ADHD and how this can be encouraged and supported.

A Bayesian computational model to investigate expert anticipation of a seemingly unpredictable ball bounce.

During dynamic and time-constrained sporting tasks performers rely on both online perceptual information and prior contextual knowledge to make effective anticipatory judgments. It has been suggested that performers may integrate these sources of information in an approximately Bayesian fashion, by weighting available information sources according to their expected precision. In the present work, we extended Bayesian brain approaches to anticipation by using formal computational models to estimate how performers weighted different information sources when anticipating the bounce direction of a rugby ball. Both recreational (novice) and professional (expert) rugby players (n = 58) were asked to predict the bounce height of an oncoming rugby ball in a temporal occlusion paradigm. A computational model, based on a partially observable Markov decision process, was fitted to observed responses to estimate participants' weighting of online sensory cues and prior beliefs about ball bounce height. The results showed that experts were more sensitive to online sensory information, but that neither experts nor novices relied heavily on prior beliefs about ball trajectories in this task. Experts, but not novices, were observed to down-weight priors in their anticipatory decisions as later and more precise visual cues emerged, as predicted by Bayesian and active inference accounts of perception.

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.

Cognitive, Psychophysiological, and Perceptual Responses to a Repeated Military-Specific Load Carriage Treadmill Simulation.

BACKGROUND: Dismounted military operations require soldiers to complete cognitive tasks whilst undertaking demanding and repeated physical taskings. OBJECTIVE: To assess the effects of repeated fast load carriage bouts on cognitive performance, perceptual responses, and psychophysiological markers. METHODS: Twelve civilian males (age, 28 ± 8 y; stature, 186 ± 6 cm; body mass 84.3 ± 11.1 kg; V̇O2max, 51.5 ± 6.4 mL·kg-1·min-1) completed three ∼65-min bouts of a Fast Load Carriage Protocol (FLCP), each interspersed with a 65-min recovery period, carrying a representative combat load of 25 kg. During each FLCP, cognitive function was assessed using a Shoot/Don't-Shoot Task (SDST) and a Military-Specific Auditory N-Back Task (MSANT), along with subjective ratings. Additional psychophysiological markers (heart rate variability, salivary cortisol, and dehydroepiandrosterone-sulfate concentrations) were also measured. RESULTS: A main effect of bout on MSANT combined score metric (p < .001, Kendall's W = 69.084) and for time on the accuracy-speed trade-off parameter of the SDST (p = .025, Ñ 2 = .024) was evident. These likely changes in cognitive performance were coupled with subjective data indicating that participants perceived that they increased their mental effort to maintain cognitive performance (bout: p < .001, Ñ 2 = .045; time: p < .001, Ñ 2 = .232). Changes in HRV and salivary markers were also evident, likely tracking increased stress. CONCLUSION: Despite the increase in physiological and psychological stress, cognitive performance was largely maintained; purportedly a result of increased mental effort. APPLICATION: Given the likely increase in dual-task interference in the field environment compared with the laboratory, military commanders should seek approaches to manage cognitive load where possible, to maintain soldier performance.

Player Perceptions of Face Validity and Fidelity in 360-Video and Virtual Reality Cricket.

Virtual reality (VR) and 360° video can provide new opportunities for testing and training in sport. Both options offer different benefits in terms of efficacy for training, ease of use, and cost. This creates questions about the implementation of immersive technologies, and research is required to further understand their use. We aimed to gain initial evidence of athletes' perceptions of face validity and fidelity in VR and 360-video. Thirty-nine international pathway cricketers experienced five overs in VR cricket and in a 360-video recording. After trying each technology, players completed questionnaires to measure perceptions of presence and task workload. Participants reported immersive experience in both methods, but higher levels of realism, possibility to act, physical effort, temporal constraints, and task control in VR. 360-video offers a better possibility to visually examine the environment, while VR offers enhanced realism and physical elements, but 360-video may still offer affordable solutions for visual tasks.

An Examination of the Challenge/Threat State and Sport-Performance Relationship While Controlling for Past Performance.

A challenge state is associated with superior performance compared to a threat state in a variety of performance domains (e.g., sport, aviation, education). However, in the challenge and threat (C/T) literature, between-subjects variability in past performance is often inconsistently controlled for. Here, we aimed to investigate the effects of C/T states on performance using two methods to control for past performance. Experiment 1 used previous performance statistics in a between-subjects design and Experiment 2 used a within-subject design. In Experiment 1, regression analysis showed that cardiovascular correlates of C/T states predicted cricket batting performance in 45 amateur cricketers. In Experiment 2, between- and within-subject analysis found that past performance was the only predictor of subsequent golf putting performance in 40 noncompetitive golfers. Taken together, the findings challenge the role that C/T states play in predicting performance under pressure after controlling for past performance.

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.

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.

Context Affects Quiet Eye Duration and Motor Performance Independent of Cognitive Effort.

Extensive literature has shown the effect of "quiet eye" (QE) on motor performance. However, little attention has been paid to the context in which tasks are executed (independent of anxiety) and the mechanisms that underpin the phenomenon. Here, the authors aimed to investigate the effects of context (independent of anxiety) on QE and performance while examining if the mechanisms underpinning QE are rooted in cognitive effort. In this study, 21 novice participants completed golf putts while pupil dilation, QE duration, and putting accuracy were measured. Results showed that putting to win was more accurate compared with the control (no context) condition, and QE duration was longer when putting to win or tie a hole compared with control. There was no effect of context on pupil dilation. Results suggest that, while the task was challenging, performance scenarios can enhance representativeness of practice without adding additional load to cognitive resources, even for novice performers.

Why do bad balls get wickets? The role of congruent and incongruent information in anticipation.

Skilled anticipation is underpinned by the use of kinematic and contextual information. However, few researchers have examined what happens when contextual information suggests an outcome that is different from the event that follows. We aimed to bridge this gap by manipulating the relationship between contextual information and final ball location in a cricket-batting task. We predicted that when contextual information is congruent with the eventual outcome then anticipation would be facilitated. In contrast, when contextual information is incongruent, this would lead to a confirmation bias on kinematic information and result in decreased anticipation accuracy. We expected this effect to be larger in skilled performers who are more able to utilise context. Skilled and less-skilled cricket batters anticipated deliveries presented using a temporally occluded video-based task. We created conditions whereby contextual information and event outcome were either congruent or incongruent. There was a significant skill by condition interaction (p < 0.05). The skilled group anticipated significantly more accurately than the less-skilled group on the congruent trials. Both groups anticipated less accurately on incongruent trials, with the skilled participants being more negatively affected. Skilled performers prioritise contextual information and confirmation bias affects the use of kinematic information available later in the action.

The effect of consistent and varied follow-through practice schedules on learning a table tennis backhand.

In table tennis the follow-through action after a shot is an important part of skill execution. In this experiment, we aimed to extend literature around the contextual interference effect by investigating whether the way the follow-through is organised in practice affects learning of the backhand shot in table tennis. Thirty unskilled participants were allocated to blocked-variable practice, random-variable practice or a control-constant group and aimed backhand shots towards a target following ball projection from a machine. Each group completed these shots in a pre-test, a training phase with follow-through manipulations, a post-test, and a retention test. The random-variable group improved their shot accuracy from pre-test to post-test and from pre-test to retention test (both P < 0.01, d = 1.03), whereas neither the blocked-variable nor the control-constant group displayed any change in shot accuracy. Practising the follow-through in a random-variable fashion enhanced learning of the preceding shot compared with blocked-variable practice or no follow-through instructions. The benefits of learning motor skills under conditions of high contextual interference also apply to how follow-through actions are organised. The findings are valuable to coaches and suggest that instructions related to the follow-through action should be considered as well as the primary skill itself.

The effects of anxiety and situation-specific context on perceptual-motor skill: a multi-level investigation.

We examined the effects of anxiety and situation-specific contextual information on attentional, interpretational, and behavioural processes underpinning perceptual-motor performance as proposed by Nieuwenhuys and Oudejans (Psychological Research 76:747-759; Nieuwenhuys, Oudejans, Psychological Research 76:747-759, 2012) using an in situ task. Twelve skilled cricket batsmen played against a skilled spin bowler under conditions manipulated to induce low and high levels of anxiety and the presence of low and high levels of situation-specific context. High anxiety decreased the number of good bat-ball contacts, while high levels of situation-specific context increased the number of times the ball was missed. When under high anxiety, participants employed significantly more fixations of shorter duration to more locations, but the effects of anxiety were restricted to the attentional level only. Situation-specific context affected performance and behavioural measures but not anxiety, cognitive load or perceptual-cognitive processes, suggesting that performance is influenced through different mechanisms from anxiety that are independent of working memory load.

"What we talk about is creating a probability": Exploring the interaction between the anticipation and decision-making processes of professional bowlers and batters in Twenty20 cricket.

Expert performers in time constrained sports use a range of information sources to facilitate anticipatory and decision-making processes. However, research has often focused on responders such as batters, goalkeepers, defenders, and returners of serve, and failed to capture the complex interaction between opponents, where responders can also manipulate probabilities in their favour. This investigation aimed to explore the interaction between top order batters and fast or medium paced bowlers in cricket and the information they use to inform their anticipatory and decision-making skills in Twenty20 competition. Eleven professional cricketers were interviewed (8 batters and 3 bowlers) using semi-structured questions and scenarios from Twenty20 matches. An inductive and deductive thematic analysis was conducted using the overarching themes of Situation Awareness (SA) and Option Awareness (OA). Within SA, the sub-themes identified related to information sources used by bowlers and batters (i.e., stable contextual information, dynamic contextual information, kinematic information). Within OA, the sub-themes identified highlighted how cricketers use these information sources to understand the options available and the likelihood of success associated with each option (e.g., risk and reward, personal strengths). A sub-theme of 'responder manipulation' was also identified within OA to provide insight into how batters and bowlers interact in a cat-and-mouse like manner to generate options that manipulate one another throughout the competition. A schematic has been developed based on the study findings to illustrate the complex interaction between the anticipation and decision-making processes of professional top order batters and fast or medium paced bowlers in Twenty20 cricket.

The effect of task load, information reliability and interdependency on anticipation performance.

In sport, coaches often explicitly provide athletes with stable contextual information related to opponent action preferences to enhance anticipation performance. This information can be dependent on, or independent of, dynamic contextual information that only emerges during the sequence of play (e.g. opponent positioning). The interdependency between contextual information sources, and the associated cognitive demands of integrating information sources during anticipation, has not yet been systematically examined. We used a temporal occlusion paradigm to alter the reliability of contextual and kinematic information during the early, mid- and final phases of a two-versus-two soccer anticipation task. A dual-task paradigm was incorporated to investigate the impact of task load on skilled soccer players' ability to integrate information and update their judgements in each phase. Across conditions, participants received no contextual information (control) or stable contextual information (opponent preferences) that was dependent on, or independent of, dynamic contextual information (opponent positioning). As predicted, participants used reliable contextual and kinematic information to enhance anticipation. Further exploratory analysis suggested that increased task load detrimentally affected anticipation accuracy but only when both reliable contextual and kinematic information were available for integration in the final phase. This effect was observed irrespective of whether the stable contextual information was dependent on, or independent of, dynamic contextual information. Findings suggest that updating anticipatory judgements in the final phase of a sequence of play based on the integration of reliable contextual and kinematic information requires cognitive resources.

The effects of simulated monocular and binocular vision impairment on football penalty kick performance.

Sports performance is relatively robust under high levels of binocular blur. However, the limited research studies investigating monocular impairments has shown it has a larger impact on sport performance. This research study is relevant for classification in sports for athletes with vision impairment (VI), where visual acuity (VA) from the better eye is used during classification. Across two experiments, we aimed to establish the point at which binocular and monocular impairments affected performance in a football penalty kick (PK) through simulating varying severities of degraded VA and contrast sensitivity (CS) in active football players. In experiment one, 25 footballers performed PKs as VA and CS were systematically decreased in both eyes, and in one condition, visual field (VF) was reduced. The most severe VA/CS condition and reduced VF significantly impacted outcome, ball velocity and placement (ball kicked closer to the centre of the goal) (p < 0.05). In experiment two, 29 different footballers performed PKs as VA and CS of only the dominant eye were systematically decreased and in one condition the dominant eye was occluded, and participants viewed their environment through the non-dominant eye (monocular viewing). No differences were observed when assessing monocular impairments influence on outcome, velocity and ball placement. PKs have a high resilience to VI, but binocular impairment has a more immediate effect, suggesting binocular measures should be used in classification processes in football.

Metabolic, cardiovascular, neuromuscular and perceptual responses to repeated military-specific load carriage treadmill simulations.

Bouts of military load carriage are rarely completed in isolation; however, limited research has investigated the physiological responses to repeated load carriage tasks. Twelve civilian men (age, 28 ± 8 years; stature, 185.6 ± 5.8 cm; body mass 84.3 ± 11.1 kg and maximal oxygen uptake, 51.5 ± 6.4 mL·kg-1 min-1) attended the laboratory on two occasions to undertake a familiarisation and an experimental session. Following their familiarisation session, participants completed three bouts of a fast load carriage protocol (FLCP; ∼65 min), carrying 25 kg, interspersed with a 65-min recovery period. Physiological strain (oxygen uptake [V̇O2] and heart rate [HR]) was assessed during the FLCP bouts, and physical performance assessments (weighted counter-movement jump [wCMJ], maximal isometric voluntary contraction of the quadriceps [MIVC] and seated medicine ball throw [SMBT]) was measured pre and post each FLCP bout. A main effect for bout and measurement time was evident for V̇O2 and HR (both p < 0.001 and Ñ 2 = 0.103-0.816). There was no likely change in SMBT distance (p = 0.201 and Ñ 2 = 0.004), but MIVC peak force reduced by approximately 25% across measurement points (p < 0.001 and Ñ 2 = 0.133). A mean percentage change of approximately -12% from initial values was also evident for peak wCMJ height (p = 0.001 and Ñ 2 = 0.028). Collectively, these data demonstrate that repeated FLCP bouts result in an elevated physiological strain for each successive bout, along with a substantial reduction in lower body power (wCMJ and MIVC). Therefore, future research should investigate possible mitigation strategies to maintain role-related capability.