The relationship between strength asymmetries and jumping performance in professional volleyball players

Knee peak torque (PT) is associated to jump performance in volleyball players. It is not clear whether muscle strength imbalances of the knee joint can influence jump performance. The purpose of study was to analyse the association between PT and knee muscular imbalances with jump performance in professional volleyball players. Eleven elite male volleyball players (90.3 ± 9.7 kg body mass and 1.94 ± 0.06 m height) were evaluated in an isokinetic dynamometer at speeds of 60, 180 and 300 deg/s. Muscle strength imbalances were obtained through calculation of contralateral deficit between limbs and the conventional ratio (hamstrings/quadriceps). Countermovement jump (CMJ) was performed on a force plate to calculate mechanical power and height. Association was found between knee extensor PT at 180 deg/s with CMJ power (r = 0.610, p = 0.046). Conventional ratio at 300 deg/s showed negative association with CMJ (r = ?0.656, p = 0.029). The optimal ratio between knee extensors PT in relation to the flexors PT is associated with the greater mechanical power in CMJ. Contralateral deficit does not seem to be associated with the CMJ performance. Considering the knee extensor PT is associated with CMJ power, our findings suggest that strength-based training in volleyball athletes should not omit the conventional muscle ratio.     

Carbon outclasses wood in racket paddles: Ratings of expert and intermediate tennis players

Wooden racket paddles were modified with rubber and carbon fibre laminates and their differences tested in terms of flexural, damping, and coefficient of restitution properties. Four rackets types were designed: a wood reference, wood with rubber, carbon fibre 0°, and carbon fibre 90°. Seven expert and eight intermediate tennis players tested the rackets. To determine which of the four rackets suited the players best, we asked the players to compare the rackets two by two. After each pair tested, participants had to fill out a 4-item questionnaire in which different aspects of the rackets' performance were judged. The most preferred racket was the 0° carbon fibre racket, followed by the 90° carbon fibre racket, the wood racket and, finally, the 1-mm rubber racket. Thus, rackets with the highest stiffness, least damping, and highest coefficient of restitution were the most preferred. Interestingly, although experts and intermediate players overall judged the rackets in very similar ways according to force, vibration, and control, they were sensitive to quite different physical characteristics of the rackets.     

Leadership development in Higher Education: A literature review and implications for programme redesign

Leadership development (LD) activity and its effectiveness has not been explored rigorously across changing university settings globally. As Higher Education settings change radically throughout the world, Higher Education professionals are operating in more uncertain environments, and leaders are taking increasingly complex and diverse approaches to their leadership roles. LD activities therefore become important in supporting this highly complex context, yet little is known in the literature about LD and its impact in Higher Education. We examine peer‐reviewed work on LD in Higher Education settings globally to understand what may be learned about its content, processes, outcomes and impact. Our results suggest the current literature is small‐scale, fragmented and often theoretically weak, with many different and coexisting models, approaches and methods, and little consensus on what may be suitable and effective in the Higher Education context. We reflect on this state of play and develop a novel theoretical approach for designing LD activity in Higher Education institutions.     

Reading with a Crayon: Pre-conventional Marginalia as Reader Response in Early Childhood

Child-produced marginalia, annotations written or drawn in the margins of a text by a young reader, have been stigmatized as devaluing the book on which it was created and often dismissed as “graffiti.” Recent historical studies of marginalia created by older children, those who have mastered conventional writing and drawing, have challenged this notion by looking at extratextual annotations as a means to understanding children’s diverse uses of books as both intellectual and physical objects. However, pre-conventional scribbles on books by very young children have not been explored as artifacts of emergent literacy practices or reader response. Yet, scholarship in the fields of literacy education, art education, early childhood education and theories of place suggest that children can develop expectations for books in the first few years of life and that their earliest drawing experiences show evidence of intentionality. This reader response study draws from video data of three-year-old Elijah and his eighteen-month-old sister, Hannah, to explore the production, of pre-conventional marginalia in early childhood. The findings of this study suggest that toddlers and preschool-aged children can understand books as distinct and pleasurable artifacts in their immediate environments, that the marks they make in their picturebooks are evidence of reader response, that the act of drawing enables them to engage in a fictional landscape, and that pre-conventional marginalia can provide us with insight into very young children’s earliest aesthetic responses to texts.