82 research outputs found

    Training for “worst-case” scenarios in sidestepping: Unifying strength and conditioning and perception–action approaches

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    Sidesteps can impose high demands on the knee joint and lead to non-contact anterior cruciate ligament (ACL) injuries. Understanding how different constraints shape an athlete’s movement strategy and the associated joint demands can help design training interventions to increase injury resilience. Motor capacities, such as muscular strength and power, act as boundaries for the safe execution of perceptual–motor skills and co-determine the emergence of unique movement strategies. Increasing single- and multi-joint strength enables a broader solution space for movement strategies and increases load tolerance. Manipulating task constraints during sidesteps can be used in the training process to systematically expose athletes to increasing demands (on the knee joint or any joint or structure) in preparation for “worst-case” scenarios. In particular, the type and timing of information available influence the preparation time, subsequently affecting the movement strategy and the associated magnitude of external knee joint loading (e.g., knee valgus moment). While an athlete’s perceptual–cognitive skills contribute to the preparation time during in situ scenarios, attempts to further improve those skills with the aim of increasing athlete preparation time prior to “worst-case” scenarios are yet to demonstrate conclusive evidence of transfer to on-field situations. Therefore, in the current article, we reflect on the impact of different interacting constraints that influence the execution of sidesteps during in situ scenarios and impose high demands on the knee joint. Subsequently, we discuss how an integrated perspective, drawing on knowledge and perspectives from strength and conditioning and perception–action, may enhance an athlete’s ability to withstand “worst-case” scenarios and adapt to perform varied movement executions when sidestepping

    A SYSTEMATIC REVIEW OF METHODOLOGIES USED TO ASSESS “UNANTICIPATED” CUTTING MECHANICS

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    Biomechanical analysis of cutting mechanics is a popular approach to assessing risk factors for injuries such as anterior cruciate ligament ruptures. The purpose of this study was to systematically review the methodological approaches to assessing unanticipated cutting mechanics and provide a review of such approaches. A total of 93 articles where identified that had assessed unanticipated cutting. The most common methodological design was a 45° cutting task following a run-up where the direction of the cut was determined by a light-based stimulus. External light stimuli create a worst-case scenario by providing information about the task at the last moment meaning opportunity for preparatory mechanics is limited. However, light stimuli do not allow for perception-action to take place and may therefore not truly reflect an athlete’s cutting mechanics

    Managing farmed landscapes for pollinating insects

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    Increasing floral resources and improving habitat conditions can benefit pollinating insect species, wildflowers and crop production

    Developmental pathways in netball match officiating:Examining the potential role of technology

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    Research aim: This research sought to explore the role of technology within development pathways in netball match officiating.Research methods: A qualitative methodology was employed to gain insight into technology within development pathways. 28 participants were sampled across the five global netball regions, fulfilling single and mixed umpiring (N = 21), assessing (N = 7), coaching (N = 5), tutoring (N = 5), mentoring (N = 3), administration (N = 3), and bench officiating (N = 1) roles, with thematic analysis using inductive coding adopted to investigate perspectives specifically towards technology use.Results and findings: Video within assessment processes and its implementation in analysis practices was highlighted as important for providing effective feedback. The effect might not be due to the technology alone and interactions between the individuals providing and receiving feedback should also be considered. Creating learning provision, enabling the sharing of resources and greater access to development opportunities were discussed as crucial, especially in developing world regions. However, socio-cultural differences might impact upon personal preferences in using technology or its perceived need, and regular monitoring of provision is crucial to ensure impact is occurring. Adopting processes to share knowledge across regions and creating greater assessment and mentoring opportunities were also seen to enhance development and learning. Implementation of technology should be considered in relation to different stages of development that are apparent across nations, with factors such as cost, required skills, and the compatibility being crucial to ensuring needs are met appropriately.Implications: The findings identify how technology could act to benefit match officiating pathways. The crucial factor is ensuring that equity is sought in providing mechanisms of this manner, adopting policies that are aimed at effecting the global development landscape. This might, however, be impacted by cost and availability, and as such considerations need to be made towards accessible opportunities, irrespective of geographical location.Research contribution: This research provides detail on the role of technology within development processes of sport officials and in a previously under researched sport

    The use of embedded context-sensitive attractors for clinical walking test guidance in virtual reality

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    Virtual reality is increasingly used in rehabilitation and can provide additional motivation when working towards therapeutic goals. However, a particular problem for patients regards their ability to plan routes in unfamiliar environments. Therefore, the aim of this study was to explore how visual cues, namely embedded context-sensitive attractors, can guide attention and walking direction in VR, for clinical walking interventions. This study was designed using a butterfly as the embedded context- sensitive attractor, to guide participant locomotion around the clinical figure of eight walk test, to limit the use of verbal instructions. We investigated the effect of varying the number of attractors for figure of eight path following, and whether there are any negative impacts on perceived autonomy or workload. A total of 24 participants took part in the study and completed six attractor conditions in a counterbalanced order. They also experienced a control VE (no attractors) at the beginning and end of the protocol. Each VE condition lasted a duration of 1 minute and manipulated the number of attractors to either singular or multiple alongside, the placement of turning markers (virtual trees) used to represent the cones used in clinical settings for the figure of eight walk test. Results suggested that embedded context-sensitive attractors can be used to guide walking direction, following a figure of eight in VR without impacting perceived autonomy, and workload. However, there appears to be a saturation point, with regards to effectiveness of attractors. Too few objects in a VE may reduce feelings of intrinsic motivation, and too many objects in a VE may reduce the effectiveness of attractors for guiding individuals along a figure of eight path. We conclude by indicating future research directions, for attractors and their use as a guide for walking direction

    Goalkeeping in the soccer penalty kick: it is time we take affordance-based control seriously!

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    The goalkeeper’s difficulty in the soccer penalty kick originates from the extreme spatiotemporal constraints of the situation. The present review claims that the current understanding is biased toward attributing a goalkeeper’s success in saving a penalty kick to perceptual-cognitive skill. To investigate the goalkeeper’s skill, researchers have often adopted video tasks. In doing so, they studied perceptual skill in isolation from action. We use affordance-based control theory to propose an alternative understanding and research methodology. We argue that goalkeepers in the penalty kick situation should regulate their actions in ways that sustain the perception of stoppability. To capture this, we outline the building blocks for a required lateral velocity model, in which the goalkeepers’ required actions are scaled to their maximum capabilities. In doing so, we provide new directions for research

    A novel on-field training intervention improves novice goalkeeper penalty kick performance

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    This study developed an on-field anticipation training intervention with the aim of improving novice goalkeeper penalty kick performance. Eighteen participants were allocated to either one-player (OP); or three-player (TP) training. The OP group faced “traditional” practice, with one player running-up to execute each kick. The TP group faced three players in a form of variable practice; two players stopped their run-up approximately 1.2m from the ball with the third-player executing the kick. Following training, results revealed that TP made significantly more saves when facing non-deception kicks in comparison with OP. An implication for applied practice is that there are potential gains to be made through training anticipation skills via new on-field practices rather than the current research focus on video-based training

    Nothing magical:pantomimed grasping is controlled by the ventral system

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    In a recent amendment to the two-visual-system model, it has been proposed that actions must result in tactile contact with the goal object for the dorsal system to become engaged (Whitwell et al., Neuropsychologia 55:41-50, 2014). The present study tested this addition by assessing the use of allocentric information in normal and pantomime actions. To this end, magicians, and participants who were inexperienced in performing pantomime actions made normal and pantomime grasps toward objects embedded in the MĂŒller-Lyer illusion. During pantomime grasping, a grasp was made next to an object that was in full view (i.e., a displaced pantomime grasping task). The results showed that pantomime grasps took longer, were slower, and had smaller hand apertures than normal grasping. Most importantly, hand apertures were affected by the illusion during pantomime grasping but not in normal grasping, indicating that displaced pantomime grasping is based on allocentric information. This was true for participants without experience in performing pantomime grasps as well as for magicians with experience in pantomiming. The finding that the illusory bias is limited to pantomime grasping and persists with experience supports the conjecture that the normal engagement of the dorsal system's contribution requires tactile contact with a goal object. If no tactile contact is made, then movement control shifts toward the ventral system
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