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1.
Abstract Swain (1997) employed the mathematical model of Di Prampero et al. (1979) to predict that, for cycling time-trials, the optimal pacing strategy is to vary power in parallel with the changes experienced in gradient and wind speed. We used a more up-to-date mathematical model with validated coefficients (Martin et al., 1998) to quantify the time savings that would result from such optimization of pacing strategy. A hypothetical cyclist (mass = 70 kg) and bicycle (mass = 10 kg) were studied under varying hypothetical wind velocities (?10 to 10 m · s?1), gradients (?10 to 10%), and pacing strategies. Mean rider power outputs of 164, 289, and 394 W were chosen to mirror baseline performances studied previously. The three race scenarios were: (i) a 10-km time-trial with alternating 1-km sections of 10% and ?10% gradient; (ii) a 40-km time-trial with alternating 5-km sections of 4.4 and ?4.4 m · s?1 wind (Swain, 1997); and (iii) the 40-km time-trial delimited by Jeukendrup and Martin (2001). Varying a mean power of 289 W by ± 10% during Swain's (1997) hilly and windy courses resulted in time savings of 126 and 51 s, respectively. Time savings for most race scenarios were greater than those suggested by Swain (1997). For a mean power of 289 W over the “standard” 40-km time-trial, a time saving of 26 s was observed with a power variability of 10%. The largest time savings were found for the hypothetical riders with the lowest mean power output who could vary power to the greatest extent. Our findings confirm that time savings are possible in cycling time-trials if the rider varies power in parallel with hill gradient and wind direction. With a more recent mathematical model, we found slightly greater time savings than those reported by Swain (1997). These time savings compared favourably with the predicted benefits of interventions such as altitude training or ingestion of carbohydrate-electrolyte drinks. Nevertheless, the extent to which such power output variations can be tolerated by a cyclist during a time-trial is still unclear. 相似文献
2.
Gökçe Erturan İlker Yunus Arslan Gıyasettin Demirhan 《Measurement in physical education and exercise science》2013,17(4):301-313
The Trichotomous Achievement Goal Scale was developed by Agbuga and Xiang (2008) by including selected items from the scales of Duda and Nicholls (1992), Elliot (1999), and Elliot and Church (1997) and adapting them into Turkish. The scale consists of 18 items, and students rated each item on a 7-point Likert scale. To ascertain the validity and reliability of the Trichotomous Achievement Goal Scale, it was administered to 845 female and 861 male Turkish high school students attending three public schools in the 2008–2009 spring semester. Exploratory and confirmatory factor analyses were conducted, and Cronbach's alpha and Fornell and Larcker's (1981) criteria were tested on the items that measured the students' achievements, screening for the three distinct types of achievement goals proposed by the trichotomous framework. Based on the results of the study, the 16-item Trichotomous Achievement Goal Scale can be claimed as a valid a reliable scale. 相似文献
3.
Abstract Oudejans, Bakker, and Beek (2007) recognize several relevant aspects of offside judgements in association football in the paper by Helsen, Gilis, and Weston (2006). We agree that the existing knowledge base on offside assessment needs to be expanded for two reasons. First, from a theoretical point of view it is important to examine how assistant referees can learn to deal with the limitations of the human visual information processing system. Second, from a practical point of view it is relevant to understand better refereeing performances and to identify potential explanations for incorrect offside decisions that could impact on the final outcome of the game. Oudejans et al. (2007) believe we both misinterpreted the optical error hypothesis and that our data set was unsuited to test it. Below, we react to these comments. 相似文献
4.
Abstract This study documents the effect of players' dismissals on team performance in professional soccer. Our aim was to determine whether the punishment meted out for unacceptable player behaviour results in reduced team performance. The official web site of the German Soccer Association was used for coding data from games played in the first Bundesliga between the 1963 – 64 and 2003 – 04 (n = 41) seasons. A sample of 743 games where at least one red card was issued was used to test hypotheses derived from crisis theory (Bar-Eli & Tenenbaum, 1989a). Players' dismissals weaken a sanctioned team in terms of the goals and final score following the punishment. The chances of a sanctioned team scoring or winning were substantially reduced following the sanction. Most cards were issued in the later stages of matches. The statistics pertaining to outcome results as a function of game standing, game location, and time phases – all strongly support the view that teams can be considered conceptually similar to individuals regarding the link between stress and performance. To further develop the concept of team and individual psychological performance crisis in competition, it is recommended that reversal theory (Apter, 1982) and self-monitoring and distraction theories (Baumeister, 1984) be included in the design of future investigations pertaining to choking under pressure. 相似文献
5.
Initial teacher education (ITE) students participate in various workplaces within schools and in doing so, form understandings about the numerous, and at times competing, expectations of teachers’ work. Through these experiences they form understandings about themselves as health and physical education (HPE) teachers. This paper examines the ways communities of practice within HPE subject department offices function as sites of workplace learning for student teachers. In particular this research focused on how ITE students negotiate tacit and contradictory expectations as well as social tasks during the practicum and the ways in which their understandings are mediated through participation in the workspace. Qualitative methods of survey and semi-structured interview were used to collect data on a cohort of student teachers during and following their major (10 week) practicum experience. Analysis was informed by theories of communities of practice (Wenger, 1998), workplace learning (Billett, 2001), and social task systems (Doyle, 1977). It was evident that considerable effort, attention, and energy was expended on various interrelated social tasks aimed at building positive relationships with their supervisor and other HPE teachers at the school. The social dynamics were highly nuanced and required a game-like approach. In our view the complexity that student teachers must negotiate in striving for an excellent evaluation warrants specific attention in physical education teacher education (PETE) programs. This study raises questions regarding our responsibilities in sending student teachers into contexts that might even be described as toxic. We offer some suggestions for how PETE might better support students going into practicum contexts that might be regarded as problematic workplaces. 相似文献
6.
Camilla J. Knight Ian L. Reade Anne-Marie Selzler Wendy M. Rodgers 《Journal of sports sciences》2013,31(10):1054-1063
Abstract Coaching has been recognised as a demanding occupation, associated with a range of stressors. The extent to which coaches perceive stress is likely to be influenced by various personal and situational factors. The purpose of this study was to identify coaches' levels of perceived stress and examine the personal and situational factors that may influence coaches' perceptions of stress. In total, 502 coaches working with university, college, Canada Games, and/or nationally identified athletes completed this study. Coaches completed an online survey, which included questions regarding demographics, work/job-related considerations, and aspects relating to their contract. Coaches also completed the Perceived Stress Scale (Cohen, Kamarck, & Mermelstein, 1983). Overall coaches indicated slightly below average levels of perceived stress (M = 15.13 out of 40) compared with norm-values (Cohen & Janicki-Deverts, 2012). Demographic factors, job-related characteristics, and certain aspects of their contract were associated with coaches' perceptions of stress. In particular, unclear expectations, long-working hours (>40), lack of agreed evaluation criteria, higher salaries, and a lack of social support were related to higher perceptions of stress. As such, the findings of the current study indicate that a reduction in perceived stress is likely to be achieved through a multifaceted approach that addresses multiple factors associated with coaching. 相似文献
7.
Natalie Kalmet 《Measurement in physical education and exercise science》2013,17(2):88-112
This study assessed the performance of the original version of the Physical Self-Perception Profile (PSPP; Fox & Corbin, 1989) as compared to a revised version. University students (N?=?259) participated in the study, each answering and comparing the clarity of the original and a revised PSPP. While participants found the revised version to be significantly clearer, it performed similarly to the original in select analyses of internal consistency and construct validity. The original structured alternative format did not have lower levels of socially desirable responding, as compared to the Likert-type ordered response scale format of the revised PSPP. Because the revised version was deemed clearer, performed similarly to the original on select psychometric analyses, and did not have any data loss, there is merit in further examining additional validity and reliability evidence for the revised PSPP. 相似文献
8.
Bart Gilis Peter Catteeuw Evelien Van Roie Johan Wagemans 《Journal of sports sciences》2013,31(6):551-563
Abstract Baldo et al. (2002) and Helsen et al. (2006) considered the flash-lag effect to explain errors made by assistant referees when judging offside in association football. The main aims of the present study were as follows: (1) to determine whether the flash-lag effect emerges in offside situations on the field of play or off the field when presented as computer animations or as video footage of real-life matches; (2) to examine offside decision-making errors in two standards of assistant referee – international FIFA and Belgian national referees. The results support the flash-lag hypothesis in several ways. First, both the FIFA and Belgian assistant referees were more likely to make errors by raising their flag when they had to assess offside situations on the field of play and when presented as three-a-side computer animations. Second, more flag errors were made when the defender moved in the opposite direction to that of the attacker. Third, the strategy of raising the flag in case of doubt was not observed when an interpretation of the offside law had to be made about the involvement of play of an attacker. Future research is needed to examine the extent to which on- and off-the-field training sessions can be used as training tools to improve offside decision-making. 相似文献
9.
Süleyman M. Yildiz 《Journal of sports sciences》2013,31(14):1493-1502
Abstract Numerous variables influence burnout, one of which is leader–member exchange. The present study was conducted to determine whether leader–member exchange quality affects burnout in professional footballers. The study used the Leader-Member Exchange-7 scale developed by Scandura and Graen (1984) to measure leader (coach)–member (player) exchange and Pines's (2005) abbreviated version of the burnout scale developed by Pines and Aronson (1988) to measure burnout. The data were obtained from the professional players (N = 107) of six football clubs in the Turkish Secondary Football League in western Turkey. The results demonstrated that quality of leader–member exchange significantly and inversely influenced burnout of professional footballers. The study also evaluated quality of leader–member exchange in terms of three strengths of relationship (low, fair, and high) between the coach and players. Contrary to expectations, the results revealed significant differences in burnout when comparing low versus fair quality and low versus high quality, while no significant difference in burnout was observed between fair and high quality. 相似文献
10.
Laurent Bosquet Antoine Duchene Paul Raoul Delhors Gregory Dupont Helen Carter 《Journal of sports sciences》2013,31(6):663-670
Abstract The aim of this study was to compare maximal accumulated oxygen deficit (hereafter O2 deficit) estimated from the methods of Whipp et al. (1986), Medbo et al. (1988), and Hill et al. (1998) to determine whether they agree sufficiently to be used interchangeably. Nineteen moderately to highly trained endurance runners first performed an incremental test to exhaustion for the determination of maximal oxygen uptake ([Vdot]O2max) and peak treadmill speed, followed by six randomly ordered constant-speed tests at 95, 100, 105, 110, 110, and 120% of peak treadmill speed. All tests were separated by at least 72 h and were performed within 4 weeks. The method of Whipp produced an O2 deficit estimate that was lower than that derived from the method of Hill or Medbo (bias ± 95% limits of agreement: ?29.6 ± 36.6 and ?26.1 ± 32.8 ml · kg?1, respectively; P < 0.001). The O2 deficit did not differ between the methods of Hill and Medbo (bias ± 95% limits of agreement: 3.5 ± 41.6 ml · kg?1; n.s.). However, poor correlations (0.21 < r < 0.33; n.s.) together with wide limits of agreement between O2 deficit estimates (70 – 80% of the mean response) clearly question using these methods interchangeably. 相似文献
11.
T. T. Toering M. T. Elferink-Gemser G. Jordet C. Visscher 《Journal of sports sciences》2013,31(14):1509-1517
Abstract In learning and development, self-regulation can be described as the extent to which individuals are metacognitively, motivationally, and behaviourally proactive participants in their learning process (Zimmerman, 1989, 2006). We examined the relationship between self-regulation and performance level in elite (n = 159) and non-elite (n = 285) youth soccer players aged 11–17 years (mean 14.5 years, s = 1.4). The players completed a questionnaire that assessed planning, self-monitoring, evaluation, reflection, effort, and self-efficacy. A logistic regression analysis was performed (controlling for age) to determine which self-regulatory aspects were associated with players' performance level (elite vs. non-elite). High scores on reflection and effort were associated with a higher level of performance. Findings suggest that elite players may be more aware of their strong and weak points as well as better able to translate this awareness into action. In addition, elite players appear to be more willing to invest effort into practice and competition. It is suggested that these better developed self-regulatory skills may translate into a more effective learning environment and ultimately result in an increased capacity for performance in elite players relative to their non-elite peers. 相似文献
12.
Abstract We analyse the evolution of the slope (critical speed) and the y-intercept (anaerobic distance capacity) of the linear distance–time relationship over a century of Olympic running performances. The distance–time relationship of each Olympic Games (1920–2004) was plotted using the performances in the 800-, 1500- and 5000-m track events. Values for critical speed and anaerobic distance capacity were determined by linear modelling. Mean performances for the 800, 1500 and 5000 m were 104.9 ± 1.5 s (1.4%), 217.2 ± 2.8 s (1.3%) and 808.9 ± 18.4 s (2.3%), respectively. Critical speed improved during the first three-quarters of the twentieth century to reach a plateau in 1984. This is in accordance with the literature (Peronnet & Thibault, 1989) and suggests that “human aerobic endurance” has improved within the century (+13.4%) and tends to stabilize. Anaerobic distance capacity was highly variable over the century (coefficient of variation = 9.4%) and did not show a linear improvement over the years as has previously been suggested (Peronnet & Thibault, 1989). This could be due to an artefact in the application of the two-parameter model to only three Olympic performances. A limitation to the use of this linear mathematical model to fit physiological data may have been demonstrated. 相似文献
13.
Jeffrey J. Martin Nate McCaughtry Sara Flory Anne Murphy Kimberlydawn Wisdom 《Measurement in physical education and exercise science》2013,17(4):274-282
The goal of the current study was to establish the factor validity of the Questionnaire Assessing School Physical Activity Environment (Robertson-Wilson, Lévesque, & Holden, 2007) using confirmatory factor analysis procedures. Another goal was to establish internal reliability and test–retest reliability. The confirmatory factor analysis results of this study supported a slightly altered version of the Questionnaire Assessing School Physical Activity Environment's school physical activity environment subscale. Internal reliability was adequate, while test–retest reliability was questionable. In brief, the pattern of findings indicated that while the original Questionnaire Assessing School Physical Activity Environment is likely adequate for some research purposes, a slightly modified version (Questionnaire Assessing School Physical Activity Environment-R) was psychometrically stronger. However, given the distinct differences in samples used in the original validation study and the current study, more research on the psychometric properties of the Questionnaire Assessing School Physical Activity Environment is needed to determine if the current results and Robertson-Wilson et al.'s (2007) results are sample specific. 相似文献
14.
Dionne Matthew 《Journal of sports sciences》2013,31(8):813-821
Abstract The aim of this study was to examine the physiological demands and movement patterns of female basketball players after changes in the rules of the game. Nine varsity players were studied during nine official games. Each game was videotaped to identify the frequencies of the main movements performed, heart rate was recorded continuously, and blood samples were collected to determine blood lactate concentration when the competition rules allowed. The main results showed that the players performed on average 652 ± 128 movements per game, which corresponded to a change in activity every 2.82 s. Mean heart rate was 165 ± 9 beats · min?1 (89.1% of maximum heart rate) for total time and 170 ± 8 beats · min?1 (92.5% of maximum) for live time. Mean blood lactate concentration was 5.2 ± 2.7 mmol · l?1 (55.9% of maximum blood lactate concentration). In addition, heart rates were significantly higher in the first half than the second half of games. These results indicate: (1) a greater physiological load compared with previous studies on female players tested before the rules modification (Beam & Merrill, 1994; McArdle et al., 1971) and (2) lower movement frequencies compared with male players competing under modern rules (Ben Abdelkrim et al., 2007). These observations must be taken into account by coaches and conditioning specialists working with female players. 相似文献
15.
Shinichi Demura Shunsuke Yamaji Takayuki Murooka Masuo Nakai 《Journal of sports sciences》2013,31(8):881-889
Abstract We previously proposed two predictive equations of visceral fat area applicable in a field setting (Demura & Sato, 2007a, 2007b). One uses the fat mass of the trunk measured by bioelectrical impedance as the main predictor (equation 1) and the other uses internal fat mass estimated from several anthropometric variables (equation 2). In this study, we examined the inter- and intra-individual accuracy of estimated values using these equations after 8 weeks of exercise training. Participants were 42 Japanese adults aged 42.7 ± 10.3 years (22 males, 20 females). Visceral fat area, body composition, and blood biochemistry were measured at baseline and after 8 weeks. There were no significant differences in reference visceral fat area measured by computed tomography and visceral fat area predicted by the equations either at baseline or after 8 weeks, and the values were highly consistent (equation 1: baseline R 2 = 0.829, after R 2 = 0.860; equation 2: baseline R 2 = 0.832; after R 2 = 0.850). No significant relationship was observed between the reference and change in visceral fat area for equation 1 (males: r = 0.272, P > 0.05; females: r = 0.428, P > 0.05), but there was a significant relationship for females with equation 2 (males: r = 0.279, P > 0.05; females: r = 0.474, P <0.05). Our findings indicate that these equations have high inter-individual consistency but low intra-individual consistency with the reference and are of limited use for the longitudinal evaluation of visceral fat area. 相似文献
16.
Robert J. Vallerand Nikos Ntoumanis Frederick L. Philippe Geneviève L. Lavigne Noémie Carbonneau Arielle Bonneville 《Journal of sports sciences》2013,31(12):1279-1293
Abstract The purpose of the present research was to test the applicability of the Dualistic Model of Passion (Vallerand et al., 2003) to being a sport (football) fan. Three studies provided support for this dualistic conceptualization of passion. Study 1 showed that harmonious passion was positively associated with adaptive behaviours (e.g. celebrate the team's victory), whereas obsessive passion was positively associated with maladaptive behaviours (e.g. risking losing one's job to go to a game). Study 2 used a short Passion Scale and showed that harmonious passion was positively related to the positive affective life of fans during the 2006 FIFA World Cup, psychological health (self-esteem and life satisfaction), and public displays of adaptive behaviours (e.g. celebrate the team's victory into the streets), whereas obsessive passion was predictive of maladaptive affective life (e.g. hating opposing teams' fans) and behaviours (e.g. mocking opposing teams' fans). Finally, Study 3 examined the role of obsessive passion as a predictor of partner's conflict that in turn undermined partner's relationship satisfaction. Overall, the present results provided support for the Dualistic Model of Passion. The conceptual and applied implications of the findings are discussed. 相似文献
17.
Caroline M. Petherick David Markland 《Measurement in physical education and exercise science》2013,17(2):55-71
The aim of this research was to develop an exercise-related goal orientation measure in an attempt to further researchers' and practitioners' current understanding of individuals' motivation to exercise for health and recreational purposes. The Goal Orientation in Exercise Measure (GOEM) was developed to assess individuals' proneness to endorse task or ego goals. Participants included 372 males and females from 16 recreational physical activity clubs in Southeast England. Confirmatory factor analysis (CFA) supported the two-factor model and demonstrated invariance between sexes. Internal consistency for task and ego subscales was .78 and .88, respectively, while correlations between the goal orientations and behavioral regulations (Markland & Tobin, 2004) served to provide initial evidence for the construct validity of the measure. The development of the GOEM may allow for a broader understanding of the motivational processes implicated in exercise-related domains. 相似文献
18.
Abstract Coping strategies are important for performance in sport and individual differences may contribute to the coping strategies adopted by athletes. In this study, we explored the main and interactive effects of the big five personality dimensions on sport-related coping and compared personality profiles of discrete groups of athletes. Altogether, 253 athletes (mean age 21.1 years, s = 3.7) completed the NEO-FFI (Costa & McCrae, 1992), and the Coping Function Questionnaire for Sport (Kowalski & Crocker, 2001). Results showed that extraverted athletes, who were also emotionally stable and open to new experiences (a three-way interaction effect), reported a greater use of problem-focused coping strategies. Conscientious athletes (main effect), and athletes displaying high levels of extraversion, openness, and agreeableness (a three-way interaction effect), reported a greater use of emotion-focused coping strategies, and athletes with low levels of openness, or high levels of neuroticism (main effects), reported a greater use of avoidance coping strategies. Different personality characteristics were observed between higher-level and lower-level athletes, between men and women athletes, and between individual and team sport athletes. These findings suggest that the five-factor model of personality can help distinguish various levels of athletic involvement and can help identify the coping strategies athletes are likely to adopt during participation. 相似文献
19.
Abstract The aims of this study were twofold: (a) to determine if dispositional achievement goal orientation profiles that are reported in the literature would be observed in a sample of youth athletes, and (b) to examine potential achievement goal orientation profile differences on perceptions of the motivational climate, perceptions of peer relationships, and motivation-related responses. Male soccer players (n = 223) aged 9–12 years (mean = 10.9, s = 0.6) completed a multi-section questionnaire containing assessments of dispositional goal (task, ego) orientations, the perceived task- and ego-involving features of the motivational climate, perceived peer acceptance and friendship quality (positive friendship quality, conflict), perceived ability, soccer enjoyment, and satisfaction with one's performance and the team. Four profiles were observed that closely matched those observed by Hodge and Petlichkoff (2000), though in the present study a lower proportion of participants exhibited achievement goal profiles consisting of relatively high ego orientation. Achievement goal profile differences were found for all variables except positive friendship quality, with a general trend for those reporting relatively lower task goal orientation to exhibit less adaptive responses. Overall, the findings support achievement goal frameworks (e.g. Nicholls, 1989) and suggest that further examination of dispositional achievement goals may afford a deeper understanding of social relationships and motivational processes in youth sport. 相似文献
20.
Larkin Lamarche Kimberley L. Gammage Philip J. Sullivan David A. Gabriel 《Measurement in physical education and exercise science》2013,17(2):120-134
This study examined the psychometric properties of the Self-Presentational Efficacy Scale (SPES) developed by Gammage, Hall, and Martin Ginis (2004). University students (196 men and 269 women) completed the SPES and measures of social physique anxiety, fear of negative evaluation, and physical activity. Participants also completed the SPES a second time. A series of multivariate data analyses were conducted to examine the SPES's factor structure. Confirmatory factor analysis indicated a 3-factor model, with each factor representing a distinct latent variable. Acceptable internal consistency and test–retest reliability were found. Evidence of concurrent validity with respect to sex and exercise status was demonstrated. Convergent validity was also shown, as relationships to exercise participation and self-presentational anxiety were found. Future research should assess the reliability and validity of the SPES in other samples and the relative and unique contribution of the three factors in predicting exercise-related outcomes. 相似文献