Scaling junior sport competition: A body-scaling approach?

The design of the junior sport competition environment plays a critical role in attracting and retaining children as life-long participants. Critically, however, the guidelines governing the design of junior sport are rarely scrutinized. With this in mind, our aim is to offer sports authorities a method to systematically assess the suitability of guidelines. The most popular junior ball sport competitions in Australia were assessed in relation to the scaling of task constraints and compared to children's corresponding physical maturation and/or performance measures. This assessment enabled the calculation of pi ratios, which were then used to categorise constraints as either (1) undersized, (2) appropriately sized or (3) oversized. Results revealed that most sports' ask children to play in oversized conditions, particularly in the under 9 to under 12 age groups and in boys' competitions. The task constraints that had the highest percentage of pi ratios appropriately sized were match duration and goal size. Comparatively, ball size and field length had the highest percentage of pi ratios classified as oversized. We contend that the systematic approach applied in this article should be used by sports authorities to understand the extent of scaling constraints in junior sport.

Examining the representativeness of a virtual reality environment for simulation of tennis performance.

There has been a growing interest in using virtual reality (VR) for training perceptual-cognitive skill in sport. For VR training to effectively simulate real-world tennis performance, it must recreate the contextual information and movement behaviours present in the real-world environment. It is therefore critical to assess the representativeness of VR prior to implementing skill training interventions. We constructed a VR tennis environment designed for training perceptual-cognitive skill, with the aim of assessing its representativeness and validating its use. Participants movement behaviours were compared when playing tennis in VR and real-world environments. When performing groundstrokes, participants frequently used the same stance in VR as they did in the real-world condition. Participants experienced a high sense of presence in VR, evident through the factors of spatial presence, engagement and ecological validity being high, with minimal negative effects found. We conclude that Tennis VR is sufficiently representative of real-world tennis. Our discussion focuses on the opportunity for training perceptual-cognitive skill and the potential for skill transfer.

Implementation of a modified sport programme to increase participation: Key stakeholder perspectives.

Modified sports, whereby equipment and rules are manipulated to facilitate skill performance, have been shown to promote skill learning and potentially increase participation. However, it is currently unexplored how key stakeholders - coaches and key figures working in National associations - who are critical stakeholders in implementing and delivering sport programmes, perceive modified sport. This study explored how tennis coaches and key figures working within tennis National associations perceived the impact of implementing a modified tennis campaign on participation and skill development in children and adults. Key figures and coaches around the world completed an online questionnaire. Both groups considered that modified tennis was positively associated with increasing and sustaining participation, skill learning, talent development and people's attitude towards tennis. Furthermore, participants thought that a rule change (i.e., use of a low-compression ball in children competitions) and the campaign's core messages (i.e., "serve, rally, score" and "easy, fun, and healthy") have been critical for the success of the campaign. These results support previous research on the positive impact of modified tennis on skill development and provide a further impetus on implementing modified sports to increase participation. Other sports can adopt similar strategies to improve their modified programmes.

Coaches' perspective towards skill acquisition in swimming: What practice approaches are typically applied in training?

This study aimed to explore the experiential knowledge and preferred training approaches of elite swimming coaches in regards to general skill development and then looking specifically at the freestyle stroke. A qualitative thematic analysis approach was employed to identify, analyse and report themes within the content of the collected data. Twenty elite swimming coaches participated in semi-structured interviews. Several themes revealed that the most common training practices employed to improve skill learning included the use of task decomposition (part-task) techniques. The findings also indicated that swimming coaches believe practice should be specific/representative to the intended performance outcomes. It is believed that such viewpoints may have been influenced by coaches' interaction with skill acquisition consultants and may have also shaped some coaches use of variants of constraints manipulation in their practice design. While swimming coaches seem to mix both traditional and contemporary skill acquisition theories in their training prescriptions, the traditional approach is dominant as evidenced by coaches seeking to reinforce "perfect" swimming technique and mechanical consistency. Considering coaches' experiential knowledge and training prescriptions may benefit future research protocols and better facilitate the transfer of empirical findings to coaching practice.

Assessment of elite junior tennis serve and return practice: A cross-sectional observation.

Practice tasks that more closely represent the demands of competition are thought to augment skill learning and transfer. This study observed the serve and return performances of junior grand slam tennis and used this benchmark to evaluate the representativeness of serve and return practice among elite junior tennis players. The serve and return behaviour of 26 junior tennis players competing in junior Australian Open grand slam matches were observed and compared with the serve and return practice behaviours of 12 elite junior tennis players over an 8-week period. The variables measured included the number of serves/returns landing in, serve/return type, serve direction and the variability of practised skills. Serve and return practice contributed to <13% of total practice time, with each skill predominately practised in isolation. Compared to the matchplay benchmark, players typically had less success (i.e., fewer serves/returns landing in the court), were less variable in shot selection and hit fewer serves to the extremities of the service box. As task representativeness increased fewer differences between practice and matchplay were observed. Tennis serve and return practice could be improved by better simulating specific competition affordances, providing greater opportunities to practice serve/return tactics and/or increasing the variability of practised skills.

A rule induction framework for the determination of representative learning design in skilled performance.

Representative learning design provides a framework for the extent to which practice simulates key elements of a performance setting. Improving both the measurement and analysis of representative learning design would allow for the refinement of sports training environments that seek to replicate competition conditions and provide additional context to the evaluation of athlete performance. Using rule induction, this study aimed to develop working models for the determination of high frequency, representative events in Australian Rules football kicking. A sample of 9005 kicks from the 2015 Australian Football League season were categorised and analysed according to the following constraints: type of pressure, kick distance, possession source, time in possession, velocity and kick target. The Apriori algorithm was used to develop two models. The first consisted of 10 rules containing the most commonly occurring constraint sets occurring during the kick in AF, with support values ranging from 0.15 to 0.22. None of the rules contained more than three constraints and confidence values ranged from 0.63 to 0.84. The second model considered ineffective and effective kick outcomes and displayed 70% classification accuracy. This research provides a measurement approach to determine the degree of representativeness of sports practice and is directly applicable to various team sports.

Enhancing skill transfer in tennis using representative learning design.

Representative Learning Design advocates that practice should simulate the demands of competition. The effectiveness of increased task representativeness to improve serving skill of junior tennis players was assessed after a six-week intervention. Thirty-three participants (15.4 ± 1.9 years of age) were assigned to one of the three groups; "serve only" (participants served to no opponent), "serve return" (participants served to an opponent and hit no extra shots) or "serve +3rd" (participants served to an opponent and hit one extra shot). Using the validated representative practice assessment tool (RPAT) tasks were considered to be low, moderate and high in task representativeness, respectively. Participants hit 56 serves, twice weekly for 6-weeks. Pre and post serving performances were assessed via a skill test and in-situ matchplay using SportsCode and HawkEye ball tracking, respectively. Serve speed, landing locations, serve angle and positional advantage was obtained for 1st and 2nd serves. The relationship between increasing representativeness and increased skill acquisition was not linear, rather different behaviours emerged. For example, when hitting 2nd serves in matchplay, the low and moderate representative groups prioritised speed over placement while the high representative group prioritised placement over speed. Coaches therefore need to carefully individualise representativeness to an athletes' specific needs.

Perception-action coupling in complex game play: Exploring the quiet eye in contested basketball jump shots.

The duration of the final fixation before movement initiation - a gaze strategy labelled quiet eye - has been found to explain differences in motor expertise and performance in precision tasks. To date, research only addressed this phenomenon in situations without adversarial constraints. In the present study, we compared the quiet-eye behaviour of intermediately-skilled and highly-skilled basketball players in defended vs. undefended game situations. We predicted differences in quiet-eye duration as a function of skill and performance particularly resulting from late quiet-eye offsets. Results indicated performance-enhancing effects of long quiet-eye durations in the defended but not in the undefended game situation. Furthermore, in line with our prediction, later quiet-eye offsets were associated with superior performance elucidating the phenomenon's relevance in online-demanding motor tasks. Further, earlier quiet-eye onsets were linked to successful performance supporting earlier suggestions that it is not only the duration but also the timing that matters. These findings not only extend the positive effects of the quiet eye in motor performance to dynamic game-play situations but also support the role of the quiet eye in response to programming and information processing respectively.

Helping coaches apply the principles of representative learning design: validation of a tennis specific practice assessment tool.

Representative Learning Design (RLD) is a framework for assessing the degree to which experimental or practice tasks simulate key aspects of specific performance environments (i.e. competition). The key premise being that when practice replicates the performance environment, skills are more likely to transfer. In applied situations, however, there is currently no simple or quick method for coaches to assess the key concepts of RLD (e.g. during on-court tasks). The aim of this study was to develop a tool for coaches to efficiently assess practice task design in tennis. A consensus-based tool was developed using a 4-round Delphi process with 10 academic and 13 tennis-coaching experts. Expert consensus was reached for the inclusion of seven items, each consisting of two sub-questions related to (i) the task goal and (ii) the relevance of the task to competition performance. The Representative Practice Assessment Tool (RPAT) is proposed for use in assessing and enhancing practice task designs in tennis to increase the functional coupling between information and movement, and to maximise the potential for skill transfer to competition contexts.

Do karate fighters use situational probability information to improve decision-making performance during on-mat tasks?

This study examined the contribution of situational probability information to the perceptual and cognitive processes underlying decision-making behaviour during in situ Karate performance. Experts and novices were required to make decisions about various attacks in different fight scenarios. The order in which the fight situations were presented was modified in order to provide advanced probability information and identify whether fighters were able to use the latter information to make better decisions. Specifically, one of the attacks was repeated every four actions. Results revealed that experts were more accurate and faster than their less skilled counterparts to block and counterattack the opponent. The experts picked up the occurrence of the attack pattern after the fifth repetition whereas novices did not. This enabled experts to improve decision time and decision accuracy. Findings suggest that such superiority could stem from the perceptual and cognitive skills possessed by the experts, thus giving them the opportunity to recognise a situation more easily. This was reinforced by gaze behaviour which demonstrated that experts used a more efficient search strategy involving fewer fixations of longer duration on a lesser number of areas relative to the novices. Moreover, experts generated more refined karate-specific knowledge structures compared with the novices.

The effect of equipment scaling on children's sport performance: the case for tennis.

The influence of scaling court-size and net height on children's tennis performance was examined. Sixteen boys (9.7 ± 0.5 years) had to perform a 30-min match in four different conditions, where court-size and/or net height were scaled by using a scaling ratio based on the differences in temporal demands between the children and the adult game. These 30-min matches were analysed using Tennis Analyst (FairPlay Ltd., Jindalee, QLD, Australia) software to determine typical tennis match performance characteristics. Children hit more winners, more forced errors, played more volleys, struck more shots from a comfortable height and played in a more forward court position when the net was scaled. Scaling both the court and net lead to a faster children's game, more closely approximating what is typical of the adult game. The differences between the typical tennis performance variables recorded suggested that scaling the net led to a more aggressive way of playing. Further, children enjoyed playing on the standard court-scaled net condition more than standard adult conditions. It is suggested that optimising the scaling of net height may be as critical as other task constraints, such as racquet length or court-size, as it leads to a more engaging learning environment for experienced children.

Scaling sporting equipment for children promotes implicit processes during performance.

This study investigated whether children who used scaled equipment compared to full size equipment during a motor task demonstrated reduced conscious involvement in performance. Children (9-11 years) performed a tennis hitting task in two attention conditions (single-task and dual-task) using two types of equipment (scaled and full size). A more skilled group and a less skilled group were formed using hitting performance scores. The more skilled group displayed greater working memory capacity than the less skilled group. For both groups, hitting performance and technique were better when scaled equipment was used. Hitting performance when using scaled equipment was not disrupted in either group by a cognitively demanding secondary task; however, performance was disrupted in the less skilled group when using full size equipment. We conclude that equipment scaling may reduce working memory engagement in motor performance and discuss the findings in the context of implicit motor learning theory.

How can novel task constraints be used to induce acute changes in gaze behaviour?

Quiet eye (QE) is a robust phenomenon in golf putting and expert players frequently demonstrate longer QE periods (i.e., the final fixation prior to the onset of the putting motion) relative to their less-skilled counterparts. In this experiment we used a pre-test/post-test design to determine whether we could use novel training aids and instructions to elicit acute changes in QE behaviour after a brief intervention. Three techniques were used: a marker under the ball, a hole-focus instruction, and a novel putting device - the putting box of science (PBoS). We compared gaze behaviour before and after 30 practice putts and found significant changes in QE duration in the absence of concomitant changes in putting performance. The control (-18 ms) and PBoS (+198 ms) groups did not change, the hole-focus group (-287 ms) had a decrease in QE duration, and the marker group (+366 ms) increased in QE duration. These finding are discussed relative to current QE training programs and the implications for development of evidence-based training aids with coach consultation.

Examining the influence of acute instructional approaches on the decision-making performance of experienced team field sport players.

We examined the influence of instructions on decision-making accuracy using video simulations of game-specific scenarios in Australian football. Skilled performers (average age of 23.4 ± 4.2 years) differing in experience (range 0 to 339 Australian Football League (AFL) matches) assumed the role of the key attacker and verbally indicated their kicking decision. Participants were randomly stratified into three groups: (1) LOOSE (n = 15)--instructed to "keep the ball away from the loose defender"; (2) TTF (n = 15) - instructed to "take the first option"; and (3) NI (control) (n = 16)--given no instructions. Gaze behaviour for a subset of participants (n = 20) was recorded. In the scenarios with an even number of attacking and defensive players, the decision-making accuracy of LOOSE was greater than TTF. This difference was most evident for lesser experienced performers, highlighting that lesser experienced performers are more affected by instructional foci than experienced performers. Gaze behaviour was not affected by instructional foci, but visual search rate was greater in scenarios of greater player number and complexity.

Do the kinematics of a baulked take-off in springboard diving differ from those of a completed dive.

Consistency and invariance in movements are traditionally viewed as essential features of skill acquisition and elite sports performance. This emphasis on the stabilization of action has resulted in important processes of adaptation in movement coordination during performance being overlooked in investigations of elite sport performance. Here we investigate whether differences exist between the movement kinematics displayed by five, elite springboard divers (age 17 ± 2.4 years) in the preparation phases of baulked and completed take-offs. The two-dimensional kinematic characteristics of the reverse somersault take-off phases (approach and hurdle) were recorded during normal training sessions and used for intra-individual analysis. All participants displayed observable differences in movement patterns at key events during the approach phase; however, the presence of similar global topological characteristics suggested that, overall, participants did not perform distinctly different movement patterns during completed and baulked dives. These findings provide a powerful rationale for coaches to consider assessing functional variability or adaptability of motor behaviour as a key criterion of successful performance in sports such as diving.

Investigating the anticipatory nature of pattern perception in sport.

The aim of the present study was to examine the anticipatory nature of pattern perception in sport by using static and moving basketball patterns across three different display types. Participants of differing skill levels were included in order to determine whether the effects would be moderated by the knowledge and experience of the observer in the same manner reported previously for simple images. The results from a pattern recognition task showed that both expert and recreational participants were more likely to anticipate the next likely state of a pattern when it was presented as a moving video, but only the experts appeared to have the depth of understanding required to elicit the same anticipatory encoding for patterns presented as schematic images. The results extend those reported in previous research and provide further evidence of an anticipatory encoding in pattern perception for images containing complex, interrelated patterns.

Validity and reliability of agility tests in junior Australian football players.

Young, W, Farrow, D, Pyne, D, McGregor, W, and Handke, T. Validity and reliability of agility tests in junior Australian football players. J Strength Cond Res 25(12): 3399-3403, 2011-The importance of sport-specific stimuli in reactive agility tests (RATs) compared to other agility tests is not known. The purpose of this research was to determine the validity and reliability of agility tests. Fifty junior Australian football players aged 15-17 years, members of either an elite junior squad (n = 35) or a secondary school team (n = 15), were assessed on a new RAT that involved a change of direction sprint in response to the movements of an attacking player projected in life size on a screen. These players also underwent the planned Australian Football League agility test, and a subgroup (n = 13) underwent a test requiring a change of direction in response to a left or right arrow stimulus. The elite players were significantly better than the school group players on the RAT (2.81 ± 0.08 seconds, 3.07 ± 0.12 seconds; difference 8.5%) but not in the arrow stimulus test or planned agility test. The data were log transformed and the reliability of the new RAT estimated using typical error (TE) expressed as a coefficient of variation. The TE for the RAT was 2.7% (2.0-4.3, 90% confidence interval) or 0.07 seconds (0.5-1.0), with an intraclass correlation coefficient (ICC) of 0.33. For the test using the arrow stimulus, the TE was 3.4% (2.4-6.2), 0.09 (0.06-0.15) seconds, and ICC was 0.10. The sport-specific stimulus provided by the new RAT is a crucial component of an agility test; however, adoption of the new RAT for routine testing is likely to require more accessible equipment and several familiarization trials to improve its reliability.

Enhancing cricket batting skill: implications for biomechanics and skill acquisition research and practice.

This review synthesises the biomechanical and skill acquisition/sport expertise literature focused on the skill of cricket batting. The literature is briefly reviewed and the major limitations, challenges, and suggested future research directions are outlined. This is designed to stimulate researchers to enhance the understanding of cricket batting biomechanics and skill acquisition and in turn assist cricket coaches develop efficacious batting skill development programmes. An interdisciplinary approach between biomechanists and skill acquisition specialists is advocated to further knowledge of the underlying processes and mechanisms of cricket batting expertise. Issues such as skill measurement, practice design, ball machines, skill transfer, the impact of Twenty/20 cricket, video simulation, and skill decomposition are discussed. The ProBatter ball machine systems are introduced along with suggestions for best practice approaches for coaches when designing batting skill development programmes.

Hitting a cricket ball: what components of the interceptive action are most linked to expertise?

Differences in interceptive skill between highly skilled and lesser skilled cricket batsmen were examined using a batting task that required participants to strike front-foot drive strokes from a machine-projected ball to a specified target. Task difficulty was manipulated by varying the width of the bat (normal, half, and third width) and target accuracy, and quality of bat-ball contact was monitored along with temporal and sequential elements of the hitting action. Analyses revealed that the highly skilled batsmen were distinguishable from less skilled counterparts by their higher accuracy under the normal and half-width bat conditions, significantly earlier initiation and completion of the front-foot stride, greater synchronization of the completion of the front-foot stride with the commencement of the downswing of the bat, and consistent timing of downswing relative to ball bounce and impact. In keeping with studies of other hitting sports, temporal and spatial coupling of the downswing to ball bounce to help minimize temporo-spatial error at the point of interception appeared critical to skilled performance. Implications for the understanding of interception and for coaching practice are briefly discussed.