Validation of an integrated experimental set-up for kinetic and kinematic three-dimensional analyses in a training environment

Biomechanical analyses using synchronized tools [electromyography (EMG), motion capture, force sensors, force platform, and digital camera] are classically performed in a laboratory environment that could influence the performance. We present a system for studying the running sprint start that synchronizes motion capture, EMG, and ground reaction force data. To maximize motion capture (Vicon 612 with six cameras), a special dim environment was created in the stadium. "Classical" tools were combined with "purpose-built" tools intended to analyse the different aspects of movement. For example, a synchronization system was built to create a common time-base for all data recordings and a portable EMG system was synchronized by a cable that was "disconnected" by the athlete's movement out of the blocks. This disconnection represented an independent event recorded by different tools. A "gap" was measured for some sprint start events between kinetic and kinematic (motion capture) data. Calibration results, measurements of time "gap", and duration of the independent event were used to validate the accuracy of motion capture and the synchronization system. The results validate the entire experimental set-up and suggest adjustment values for motion capture data. This environment can be used to study other movements and can easily be applied to several sports.     

Item analyses of the concept assessment kit-conservation for educable mentally retarded children

A series of item analyses of the CAK-C was conducted for a sample of 155 educable mentally retarded children. The probability of a correct response was found to differ from task to task, and there was evidence that the order of difficulty of the tasks for this sample resembled that for nonretarded children. The probabilities of the two incorrect responses were generally not equal, and the choice of one or the other incorrect response showed some relation to CA, MA, and IQ, particularly the last two variables.     

Integration of Multicultural Video Strategies that Transform Entertainment into Historical Film Literacy

According to many educators, textbooks will eventually be replaced by digital versions. Today's teachers, school administrators, and education policy makers are often digitally disconnected or at best digital immigrants, individuals who were born before the existence of digital technology and adopted it later in life. Unfortunately, when students enter most classrooms they are expected to turn off their digital devices and learn through textbooks and teacher-led discussions. This digital disconnect is counterproductive to cultivating film/video literacy, an innovative method that has been supported by the National Council of Social Studies (NCSS) as a means to make learning relevant and meaningful for all students in social studies classrooms. The purpose of this study is to showcase the NCSS position through two lenses: Look closely at film and video viewing strategies currently in place in social studies classrooms and point toward viewing strategies that bring engagement and deeper thinking and responses to interact with ideas and information for all students.     

Correlates of the concept assessment kit-conservation for educable mentally retarded children

The relations of the CAK-C to the Stanford-Binet and the WRAT were explored for a sample of 155 educable mentally retarded children. Correlational analyses indicated that: (a) The CAK-C is more closely related to MA than to either CA or IQ. (b) Both Reading and Arithmetic are more closely related to MA than to the CAK-C. The results support the position that Piagetian intelligence is somewhat distinct from psychometric intelligence, but suggest that the latter is the better predictor of academic achievement.     

Images of Injury: Graphic News Visuals’ Effects on Attitudes toward the Use of Unmanned Drones

In this study, sanitized coverage of the United States’ use of military drone strikes in foreign countries is pitted against more graphic news images in an experimental setting to determine effects on attitudes toward the use of U.S. military drones. In addition, multiple news exposures are tested to determine whether individuals can become emotionally inured to such coverage, even when images are more graphic. Key results find those who viewed graphic news visuals did not show evidence of desensitization after repeated viewing and expressed higher levels of concern regarding drone use but not reduced support for U.S. drone policy.     

Statistical methods for analysing discrete and categorical data recorded in performance analysis

In this paper, we identify appropriate statistical methods for analysing categorical differences in discrete variables or 'performance indicators' resulting from performance analysis. The random mechanisms associated with discrete events do not follow a normal distribution; that is, the normal distribution is a continuous not a discrete probability distribution. We propose appropriate statistical methods based on two key discrete probability distributions, the Poisson and binomial distributions. Two approaches are proposed and compared using examples from notational analysis. The first approach is based on the classic chi-square test of significance (both the goodness-of-fit test and the test of independence). The second approach adopts a more contemporary method based on log-linear and logit models fitted using the statistical software GLIM. Provided relatively simple one-way and two-way comparisons in categorical data are required, both of these approaches result in very similar conclusions. However, as soon as more complex models or higher-order comparisons are required, the approach based on log-linear and logit models is shown to be more effective. Indeed, when investigating those factors and categorical differences associated with binomial or binary response variables, such as the proportion of winners when attempting decisive shots in squash or the proportion of goals scored from all shots in association football, logit models become the only realistic method available. By applying log-linear and logit models to discrete events resulting from notational analysis, greater insight into the underlying mechanisms associated with sport performance can be achieved.     

Establishing a practical treadmill sprint as an alternative to the Wingate anaerobic test

This study examined the validity and reliability of a 30-second running sprint test using two non-motorized treadmills compared to the established Wingate Anaerobic Test. Twenty-four participants completed three sessions in a randomized order on a: (1) manual mode treadmill (Woodway); (2) specialized interval training treadmill (HiTrainer); and (3) Wingate cycle ergometer. In a subset of 15 participants, 2 additional sessions were completed on both treadmills to establish the test–retest reliability. Peak (Woodway: r = .68; HiTrainer: r = .58; p < .003), average (Woodway: r = .82; HiTrainer: r = .72, p < .001), and minimum (Woodway: r = .64; HiTrainer: r = .42, p < .043) speed indices were moderately to very strongly correlated with corresponding Wingate Anaerobic Test outputs and had excellent test–retest reliability (all intraclass correlation coefficients > .75). Fatigue index during the Wingate Anaerobic Test (51.20 ± 7.14%) was moderately correlated with the Woodway (32.9 ± 10.9%, r = .55, p = .005) only. This 30-second running sprint test may be a valid and reliable mode-specific alternative to the Wingate Anaerobic Test.     

Cultivating Conceptions of Masculinity: Television and Perceptions of Masculine Gender Role Norms

The potential of television to both reflect and shape cultural understandings of gender roles has long been the subject of social scientific inquiry. The present study employed survey methodology with 420 emerging adult respondents (18–25 years old) in a national U.S. sample to explore associations between amount of time spent viewing television and views about “ideal” masculine gender roles. The viewing of particular television genres was explored in addition to (and controlling for) overall amount of time spent with the medium, using cultivation theory as the theoretical foundation. Results showed significant statistical associations between viewing sitcoms, police and detective programs, sports, and reality television and scores on the Masculine Roles Norms Inventory–Revised scale. Biological sex of respondent (which very closely approximated gender identity in the sample) moderated a number of these relationships, with positive associations between viewing some genres and endorsement of traditional masculine gender roles stronger for biological male compared to biological female respondents.     

Science and cycling: current knowledge and future directions for research

In this holistic review of cycling science, the objectives are: (1) to identify the various human and environmental factors that influence cycling power output and velocity; (2) to discuss, with the aid of a schematic model, the often complex interrelationships between these factors; and (3) to suggest future directions for research to help clarify how cycling performance can be optimized, given different race disciplines, environments and riders. Most successful cyclists, irrespective of the race discipline, have a high maximal aerobic power output measured from an incremental test, and an ability to work at relatively high power outputs for long periods. The relationship between these characteristics and inherent physiological factors such as muscle capilliarization and muscle fibre type is complicated by inter-individual differences in selecting cadence for different race conditions. More research is needed on high-class professional riders, since they probably represent the pinnacle of natural selection for, and physiological adaptation to, endurance exercise. Recent advances in mathematical modelling and bicycle-mounted strain gauges, which can measure power directly in races, are starting to help unravel the interrelationships between the various resistive forces on the bicycle (e.g. air and rolling resistance, gravity). Interventions on rider position to optimize aerodynamics should also consider the impact on power output of the rider. All-terrain bicycle (ATB) racing is a neglected discipline in terms of the characterization of power outputs in race conditions and the modelling of the effects of the different design of bicycle frame and components on the magnitude of resistive forces. A direct application of mathematical models of cycling velocity has been in identifying optimal pacing strategies for different race conditions. Such data should, nevertheless, be considered alongside physiological optimization of power output in a race. An even distribution of power output is both physiologically and biophysically optimal for longer ( > 4 km) time-trials held in conditions of unvarying wind and gradient. For shorter races (e.g. a 1 km time-trial), an 'all out' effort from the start is advised to 'save' time during the initial phase that contributes most to total race time and to optimize the contribution of kinetic energy to race velocity. From a biophysical standpoint, the optimum pacing strategy for road time-trials may involve increasing power in headwinds and uphill sections and decreasing power in tailwinds and when travelling downhill. More research, using models and direct power measurement, is needed to elucidate fully how much such a pacing strategy might save time in a real race and how much a variable power output can be tolerated by a rider. The cyclist's diet is a multifactorial issue in itself and many researchers have tried to examine aspects of cycling nutrition (e.g. timing, amount, composition) in isolation. Only recently have researchers attempted to analyse interrelationships between dietary factors (e.g. the link between pre-race and in-race dietary effects on performance). The thermal environment is a mediating factor in choice of diet, since there may be competing interests of replacing lost fluid and depleted glycogen during and after a race. Given the prevalence of stage racing in professional cycling, more research into the influence of nutrition on repeated bouts of exercise performance and training is required.