The role of self-determined motivation in the understanding of exercise-related behaviours,cognitions and physical self-evaluations

Abstract

In this study, we investigated the adjustments to posture, kinematic and temporal characteristics of performance made by lower limb amputees during the last few strides in preparation for long jump take-off. Six male unilateral trans-femoral and seven male unilateral trans-tibial amputees competing in a World Championships final were filmed in the sagittal plane using a 100-Hz digital video camera positioned so that the last three strides to take-off were visible. After digitizing using a nine-segment model, a range of kinematic variables were computed to define technique characteristics. Both the trans-femoral and trans-tibial athletes appeared to achieve their reduction in centre of mass during the flight phase between strides, and did so mainly by extending the flight time by increasing stride length, achieved by a greater flexion of the hip joint of the touch-down leg. The trans-tibial athletes appeared to adopt a technique similar to that previously reported for able-bodied athletes. They lowered their centre of mass most on their second last stride (?1.6% of body height compared with ?1.4% on the last stride) and used a flexed knee at take-off on the last stride, but they were less able to control their downward velocity at touch-down (?0.4 m · s^?1). Both this and their restricted approach speed (8.9 m · s^?1 at touch-down), rather than technique limitations, influenced their jump performance. The trans-femoral athletes lowered their centre of mass most on the last stride (?2.3% of body height compared with ?1.6% on the second last stride) and, as they were unable to flex their prosthetic knee sufficiently, achieved this by abducting their prosthetic leg during the support phase, which led to a large downward velocity at touch-down (?0.6 m · s^?1). This, combined with their slower approach velocity (7.1 m · s^?1 at touch-down), restricted their performance.     

Perceived coach-created and peer-created motivational climates and their associations with team cohesion and athlete satisfaction: evidence from a longitudinal study

Abstract

In this longitudinal study, we examined the extent to which perceived coach- and peer-created motivational climates are associated with athlete-group cohesion and satisfaction with participation among Spanish soccer players competing in the Third National Division. Multilevel modelling analyses showed that perceived coach-created task climate was positively related to perceived cohesion and players’ satisfaction with their participation within their team. Also, perceived peer-created task climate related positively to perceived cohesion. The results indicate the importance of considering peer-related aspects of the motivational climate in addition to considering the coach-related aspects of the motivational climate when examining motivational group dynamics in sport.     

Insulin sensitivity derived from oral glucose tolerance testing in athletes: disagreement between available indices

The aims of the present study were to determine whether available "fasting" and oral glucose tolerance test-derived insulin sensitivity indices could effectively discriminate between individuals with higher than normal insulin sensitivity, and whether they would all provide similar information in clinical practice. Sprint runners (n = 8), endurance runners (n = 8) and sedentary controls (n = 7) received a 75-g oral glucose tolerance test. All participants were healthy lean males, aged 21-29 years. Besides glucose and insulin responses, a total of nine such indices were computed. Fasting as well as post-load glucose concentrations were similar in the three groups, while basal plasma insulin and the insulinaemic response to glucose were both higher in untrained individuals (at P < 0.05 and P < 0.02, respectively). There were no differences between endurance and sprint runners. The results for insulin sensitivity, however, were quite variable: three indices showed that both groups of athletes were more insulin-sensitive than controls; three indicated that this was the case for endurance runners only; one indicated that this was the case for sprint runners only; and two showed that sprint runners were more insulin-sensitive than either sedentary individuals or endurance runners (all differences were significant at P < 0.05). Controlling for total body weight or lean mass did not effectively resolve this disagreement. Apparently, the various insulin sensitivity indices examined provided different quantitative and qualitative information, despite insulin action being greater in both groups of athletes relative to controls, as reflected by their similar glucose tolerance with lower insulin concentrations. We suggest, therefore, that the use and interpretation of such indices among physically active individuals be made with caution.     

The Copyright Law Framework and Its Interaction with Open Access Repositories in Europe

The paper examines the European copyright framework and its interaction with open access repositories. Access to information resources has become a modern necessity that needs to be met to share equitably the wealth of the European society. The Directives with intellectual property provisions to enhance copyright law policy makers are the foundation of the European copyright regime. This statement helps me to clarify the design and assumptions underlying open access practice in Europe. The paper analyses strengths and short-comings of these Directives in relation to copyright protection and open access practice among European member states.     

On the cascaded Weibull fading channel model

A new stochastic fading channel model called cascaded Weibull fading is introduced and the associated capacity is derived in closed form. This model is generated by the product of independent, but not necessarily identically distributed, Weibull random variables (RVs). By quantifying the convergence rate of the central limit theorem as pertaining to the multiplication of Weibull distributed RVs, the statistical basis of the lognormal distribution is investigated. By performing Kolmogorov-Smirnov tests, the null hypothesis for this product to be approximated by the lognormal distribution is studied. Another null hypothesis is also examined for this product to be approximated by a Weibull distribution with properly adjusted statistical parameters.     

Coordination between governance actors in universities: the role of policy documents

Tertiary Education and Management - This article focuses on coordination between governance actors in a public university. The purpose of this paper is to illustrate and analyze policy documents as...     

What is the Meaning of the Physical Magnitude ‘Work’?

Usually, in physics textbooks, the physical magnitude ‘work’ is introduced as the product of a force multiplied by its displacement, in relation to the transfer of energy. In other words, ‘work’ is presented as an internal affair of physics theory, while its relation to the world of experience, that is its empirical meaning, is missing. On the other hand, in the history of its creation, ‘work’ was a concept that had empirical meaning from the start. It was constructed by engineers to measure the work (labor) of motor engines, men, and animals. Very soon however this initial meaning seems to vanish. In this article, it will be looked at how ‘work’ is presented in physics textbooks, what was its initial meaning in the history of its formulation, under what circumstances this initial meaning faded, and how elements from the history of its creation can be used in the classroom to teach it.