The long-term athlete development model: physiological evidence and application

Within the UK, the "Long Term Athlete Development" (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. The model, which is primarily a physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known as "windows of opportunity". However, it appears that there are a number of problems with this theoretical model that are not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an individualized plan for athletes. It is crucial that the LTAD model is seen as a "work in progress" and the challenge, particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid and reliable evidence.     

Development and preliminary validation of the moral authorship questionnaire

Learning Environments Research - Background When novice teachers start working in a school, it is vital that they are aware of the moral aspects of the work environment and can use their moral...     

Responding to teacher shortages: relationships among mobility experiences,attitudes, and intentions of Dutch teachers

From all over the world there have been calls from governmental institutions to address a shortage of high quality teachers. As changing jobs generates new experiences, job mobility could be a way for teachers to adhere to the government’s call to develop themselves into the teaching force needed. The research question of this study was: How do the experience with mobility and the attitude towards mobility of Dutch secondary school teachers shape their intentions to be mobile? A secondary analysis was conducted on data collected among 1261 respondents. Attitudes towards mobility were found to be linked to past experience with mobility and there is a strong relationship between the attitude towards mobility and the intention to be mobile. The control variables age, experience in teaching, and type of employment seem to have an effect as well. Implications for the teacher shortage issue are discussed.     

Impact and cost-effectiveness analysis of the national school-based sexuality education programme in Estonia

Policy-makers making decisions on the implementation of school-based sexuality education (SE) programmes face two important questions: (1) what are the costs of implementing and scaling up SE programmes, and (2) what are the impacts? This paper responds to these questions by retrospectively assessing costs, impact and cost-effectiveness of the national school-based SE programme in Estonia 1997–2009. The three-year curriculum had been taught to 190,000 students at the end of 2009. The cost of reaching one student was USD 32.90 and the total costs were USD 5.6 million. There has been a remarkable improvement in sexual health indicators in the age groups 15–19 and 20–24 years in Estonia between 2001 and 2009. During this period, annual abortions, STIs and diagnosed HIV infections in the age groups were reduced by 37%, 55% and 89%, respectively. It is difficult to assess to what extent the improvements in these sexual health indicators are attributable to the SE programme. Nevertheless, our conservative threshold analysis indicates that the Estonian SE programme could be considered cost-saving if only 4% of the observed reductions in HIV infections are attributable to the programme. There is strong evidence, therefore, to support that the Estonian school-based sexuality programme has been cost-effective.     

String tension effects on tennis ball rebound speed and accuracy during playing conditions

The primary aim of this study was to determine whether variations in rebound speed and accuracy of a tennis ball could be detected during game-simulated conditions when using three rackets strung with three string tensions. Tennis balls were projected from a ball machine towards participants who attempted to stroke the ball cross-court into the opposing singles court. The rebound speed of each impact was measured using a radar gun located behind the baseline of the court. An observer also recorded the number of balls landing in, long, wide and in the net. It was found that rebound speeds for males (110.1+/-10.2 km.h-1; mean+/-s) were slightly higher than those of females (103.6+/-8.6 km.h-1; P<0.05) and that low string tensions (180 N) produced greater rebound speeds (108.1+/-9.9 km.h-1) than high string tensions (280 N, 105.3+/-9.6 km.h-1; P<0.05). This finding is in line with laboratory results and theoretical predictions of other researchers. With respect to accuracy, the type of error made was significantly influenced by the string tension (P<0.05). This was particularly evident when considering whether the ball travelled long or landed in the net. High string tension was more likely to result in a net error, whereas low string tension was more likely to result in the ball travelling long. It was concluded that both gender and the string tension influence the speed and accuracy of the tennis ball.     

Mixed-method pre-cooling reduces physiological demand without improving performance of medium-fast bowling in the heat

This study examined physiological and performance effects of pre-cooling on medium-fast bowling in the heat. Ten, medium-fast bowlers completed two randomised trials involving either cooling (mixed-methods) or control (no cooling) interventions before a 6-over bowling spell in 31.9±2.1°C and 63.5±9.3% relative humidity. Measures included bowling performance (ball speed, accuracy and run-up speeds), physical characteristics (global positioning system monitoring and counter-movement jump height), physiological (heart rate, core temperature, skin temperature and sweat loss), biochemical (serum concentrations of damage, stress and inflammation) and perceptual variables (perceived exertion and thermal sensation). Mean ball speed (114.5±7.1 vs. 114.1±7.2 km · h(-1); P = 0.63; d = 0.09), accuracy (43.1±10.6 vs. 44.2±12.5 AU; P = 0.76; d = 0.14) and total run-up speed (19.1±4.1 vs. 19.3±3.8 km · h(-1); P = 0.66; d = 0.06) did not differ between pre-cooling and control respectively; however 20-m sprint speed between overs was 5.9±7.3% greater at Over 4 after pre-cooling (P = 0.03; d = 0.75). Pre-cooling reduced skin temperature after the intervention period (P = 0.006; d = 2.28), core temperature and pre-over heart rates throughout (P = 0.01-0.04; d = 0.96-1.74) and sweat loss by 0.4±0.3 kg (P = 0.01; d = 0.34). Mean rating of perceived exertion and thermal sensation were lower during pre-cooling trials (P = 0.004-0.03; d = 0.77-3.13). Despite no observed improvement in bowling performance, pre-cooling maintained between-over sprint speeds and blunted physiological and perceptual demands to ease the thermoregulatory demands of medium-fast bowling in hot conditions.