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Understanding factors that motivate young athletes to continue participation in sport can help key stakeholders cultivate an environment that fosters long-term participation. This investigation sought to determine the performance and participation factors that influenced continued participation in junior cricket. Administration-level data were collected each annual season across a seven-year period by a community-level junior cricket association in Australia and analysed to identify the performance and participation-based predictors of player retention. All players were males aged <16 years. Players were categorised according to whether they remained in (or departed from) the association at the end of each playing season. A multivariate logistic regression model with a stepwise variable selection was employed to identify significant independent predictors of player retention. The number of innings batted and overs bowled were significant participation-related contributors to junior cricket player retention. Performance factors such as the number of wickets taken and the number of runs scored also significantly influenced player retention. Finally, team age group, the number of previous seasons played and age were also significant factors in player retention. This demonstrates that sufficient opportunity for children to participate in the game and expression of skills competence are key factors for retention in cricket.  相似文献   
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Considering the growth in research, examining the development of mainstream sport athletes over the past two decades, studies examining development of athletes with disabilities have been surprisingly limited. While similarities in developmental trajectories between the two cohorts may exist regarding factors such as the value of practice, which tend to be universal regardless of context, disability-related issues (e.g. whether the disability was congenital or acquired) may influence the course of development, affecting variables such as starting age, training and developmental milestones. Fifty-two male and female athletes training with the Wheelchair Basketball Canada National Academy provided detailed training histories. Athletes illustrated similar developmental patterns (e.g. milestones, training adjustments) as they progressed through their sporting career. However, athletes with congenital disabilities started participation in wheelchair basketball and unorganised practice at significantly younger ages (t49?=??4.35, p?<?.001, d =?1.32; t49?=??3.49, p?<?.001, d =?1.03, respectively). While athletes with congenital disabilities continued to reach a majority of the sporting milestones at younger ages, athletes with acquired disabilities were able to reach late career milestones (e.g. national debuts) at similar ages. Athletes’ disability severity did not influence their progress through the developmental milestones and time devoted to training throughout their sporting career. Future work may consider examining developmental trajectories and training histories of athletes in various parasports to extend our understanding of their development and skill acquisition.  相似文献   
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The aim of this article was to understand how active power is used in squat and countermovement jumps. A simple empirical model comprising a mass, a spring, an active element and a damper, together with an optimisation principle, was used to identify the mechanical factors that maximise performance of jumps without countermovement (squat jumps, SJ) and with countermovement (CMJ). Twelve amateur volleyball players performed SJ from two initial positions and CMJ with two degrees of counterbalancing, while kinematic data were collected (jump height, push-off duration and position of the centre of mass). The model adjusted well to real data of SJ through all the impulse phase, and slightly less adequately at the end of this phase for CMJ. Nevertheless, it provides a satisfactory explanation for the generation and utilisation of active power for both type of jumps. On average, the estimated power of the active elements, the spring, and the damper were greater in the SJ. Based upon the result obtained with this model, we suggest that active power is best evaluated with SJ. The reason for this is that, during this kind of jump, the elements associated with the damper consume much of the energy produced by the active elements. The participation of the elements that consume the energy generated by the active elements is less in CMJ than in SJ, allowing for a better utilisation of this energy. In this way it is possible to achieve a better performance in CMJ with less active power.  相似文献   
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Limb dominance theory suggests that females tend to be more one-leg dominant and exhibit greater kinematic and kinetic leg asymmetries than their male counterparts, contributing to the increased risk of anterior cruciate ligament injury among female athletes. Thus, the purpose of this study was to examine the influences of sex and limb dominance on lower extremity joint mechanics during unilateral land-and-cut manoeuvres. Twenty-one women and 21 men completed land-and-cut manoeuvres on their dominant limb as well as their nondominant limb. Three-dimensional kinematics and kinetics were calculated bilaterally for the entire stance phase of the manoeuvre. Women performed land-and-cut manoeuvres with altered hip motions and loads as well as greater knee abduction at touchdown compared to men. Dominant limb land-and-cut manoeuvres where characterised by decreased hip flexion at touchdown as well as decreased hip flexion and adduction range of motion compared to nondominant land-and-cuts regardless of sex. The observed sex differences are consistent with previous research regarding mechanisms underlying the sex disparity in anterior cruciate ligament injury rates. However, observed differences regarding limb dominances appear somewhat arbitrary and did not suggest that the dominant or nondominant limb would be at increased risk of anterior cruciate ligament injury.  相似文献   
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