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1.
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The B-matrix method, which systematically analyses the dynamic response of non-symmetric rigid bodies, such as golf putters, is described. The three-dimensional translational and rotational accelerations of the putter face are represented by linear equations of input forces and moments represented in matrix form. The elements of the 6 × 6 B-matrix physically represent the acceleration intensity factors. This method is applied to the analysis of the putter face control mechanism. The input forces and moments are obtained by the inverse dynamics method, whilst special attention is paid to the putter face rotation, i.e. the angular acceleration around the axis of the shaft, $ \dot{w}_{ox} . $ The contribution of input forces and moments on $ \dot{w}_{ox} $ is discussed quantitatively. The results demonstrate that $ \dot{w}_{ox} $ is present even if the input force and moment are applied perpendicularly to the shaft. A cancelling mechanism to correct this motion is discussed based on the B-matrix method.  相似文献   

3.
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 Markland, D. and Tobin, V. 2004. A modification to the Behavioural Regulation in Exercise Questionnaire to include an assessment of amotivation. Journal of Sport & Exercise Psychology, 26: 191196. [Crossref], [Web of Science ®] [Google Scholar]) 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   

4.
The purpose of this study was to evaluate a new procedure of data processing from a body-mounted accelerometer to improve the assessment of vertical jump height. As the main difficulty when using an accelerometer is to detect the times of take-off and of landing, a new criterion was proposed to detect these times more accurately. Thirty physical education students participated in this study. They performed three squat jumps, three countermovement jumps with hands placed on the pelvis and three countermovement jumps with free arms ( \(n = 270\) jumps). Flight time, vertical jump height and vertical velocity at take-off were collected from the accelerometer (the Myotest device and its specific software), the modified accelerometer (raw data of the Myotest and a specific treatment for the detection take-off and landing times) and a force platform, considered as the reference device. Concerning the flight time, systematic bias decreased from \(0.034 \pm 0.079\)  s with the original accelerometer to \(-0.008 \pm 0.078\)  s with the modified accelerometer. Regarding the vertical jump height, systematic bias decreased from \(4.8 \pm 9.4\)  cm with the original accelerometer to \(-1.3 \pm 9.2\)  cm with the modified accelerometer. Finally, the vertical velocity systematic bias was \(-0.12 \pm 0.28\) and \(-0.19 \pm 0.29\)  m s \(^{-1}\) with the original accelerometer and the modified accelerometer, respectively. This study showed that the improvement proposed for the body-mounted accelerometer decreased the systematic bias, especially for the vertical jump height assessment, but not the random error.  相似文献   

5.
Abstract

Baldo et al. (2002 Baldo, M. V. C., Ranvaud, R. D. and Morya, E. 2002. Flag errors in soccer games: The flash-lag effect brought to real life. Perception, 31: 12051210. [Crossref], [PubMed], [Web of Science ®] [Google Scholar]) and Helsen et al. (2006 Helsen, W., Gilis, B. and Weston, M. 2006. Errors in judging “offside” in association football: Test of the optical error versus the perceptual flash-lag hypothesis. Journal of Sports Sciences, 24: 521528. [Taylor & Francis Online], [Web of Science ®] [Google Scholar]) 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   

6.
The present study was designed to examine the psychometric properties of the Chinese-translated Behavioral Regulation in Exercise Questionnaire-2 (Markland & Tobin, 2004 Markland, D. and Tobin, V. J. 2004. A modification of the Behavioural Regulation in Exercise Questionnaire to include an assessment of amotivation. Journal of Sport and Exercise Psychology, 26: 191196. [Crossref], [Web of Science ®] [Google Scholar]). A sample of Chinese university students (N?=?555) was invited to take part in this study. Confirmatory factor analysis was employed to examine the factorial validity, and the results supported the 5-factor structure of the Chinese-translated Behavioral Regulation in Exercise Questionnaire-2. Examination of the 95% confidence interval of the inter-factor correlations suggested that the Chinese-translated Behavioral Regulation in Exercise Questionnaire-2 assesses related but distinct constructs, which provided support for the discriminant validity. Composite reliability values of subscales were all over .75, which suggested that internal consistency reliability of Chinese-translated Behavioral Regulation in Exercise Questionnaire-2 was acceptable. Examination of the pattern of inter-factor correlations between different regulations suggested that the simplex-like pattern was displayed, which provided evidence for the nomological validity of Chinese-translated Behavioral Regulation in Exercise Questionnaire-2. Examination of the correlations of different regulations with affective and behavioral outcomes provided further support for the nomological validity. Multi-group confirmatory factor analysis was conducted to examine the gender invariance of Chinese-translated Behavioral Regulation in Exercise Questionnaire-2, and the results suggested that the factor loadings and factor variances and covariances of the Chinese-translated Behavioral Regulation in Exercise Questionnaire-2 measurement model to be invariant across male and female participants. Overall, the study provided initial psychometric evidence for the Chinese-translated Behavioral Regulation in Exercise Questionnaire-2.  相似文献   

7.
Numerous scholars have stressed the importance of personal and social responsibility in physical activity settings; however, there is a lack of instrumentation to study the implementation of responsibility-based teaching strategies. The development, content validity, and initial inter-rater reliability testing of the Tool for Assessing Responsibility-Based Education (TARE) are described here. Inter-rater agreement was calculated for paired observations focused on 2 different teachers delivering a total of 18 separate physical education lessons for students in grades 1 through 6. Findings indicate that the Tool for Assessing Responsibility-Based Education provides scores with adequate inter-rater reliability. The procedures employed in this study proved feasible and enable observers to characterize the implementation of responsibility-based teaching in physical education. The Tool for Assessing Responsibility-Based Education has numerous research and training applications relative to the Teaching Personal and Social Responsibility model (Hellison, 2003 Hellison, D. 2003. Teaching responsibility through physical activity, 2nd, 1538. Champaign, IL: Human Kinetics.  [Google Scholar]) and the national content standards for K–12 physical education, specifically Standard 5: Exhibits responsible personal and social behavior that respects self and others in physical activity settings (National Association for Sport and Physical Education, 2004 National Association for Sport and Physical Education (NASPE). 2004. Moving into the future. National standards for physical education, 2nd, 3943. Reston, VA: Author.  [Google Scholar]).  相似文献   

8.
The aim of this paper is to present a motivational model of the coach–athlete relationship that describes how coaches may influence athletes' motivation. In line with cognitive evaluation theory (Deci and Ryan, 1980 Deci EL Ryan RM 1980 The empirical exploration of intrinsic motivational processes In Advances in Experimental Social Psychology, Vol. 13 (edited by L. Berkowitz) pp. 39–80 New York: Academic Press  [Google Scholar], 1985 Deci EL Ryan RM 1985 Intrinsic Motivation and Self-Determination in Human Behavior New York: Plenum Press [Taylor & Francis Online] [Google Scholar]) and the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997 Vallerand RJ 1997 Toward a hierarchical model of intrinsic and extrinsic motivation Advances in Experimental Social Psychology 29 271 360  [Google Scholar], 2000 Vallerand RJ 2000 Deci and Ryan's self-determination theory: a view from the hierarchical model of intrinsic and extrinsic motivation Psychological Inquiry 11 312 318  [Google Scholar]), a motivational sequence is proposed where coaches' personal orientation towards coaching, the context within which they operate, and their perceptions of their athletes' behaviour and motivation influence coaches' behaviours. Also, coaches' behaviours in the form of autonomy-supportive behaviours, provision of structure and involvement have a beneficial impact on athletes' needs for autonomy, competence and relatedness, which, in turn, nurture athletes' intrinsic motivation and self-determined types of extrinsic motivation. Here, we first review coaches' autonomy-supportive behaviours. We then describe the psychological processes through which coaching behaviours have a positive influence on athletes' intrinsic and self-determined extrinsic motivation. Finally, we identify social and personality processes that determine coaching behaviours.  相似文献   

9.
The purpose of this study was to examine the underlying structure of the second edition of the Test of Gross Motor Development-2 (Ulrich, 2000 Ulrich, D. A. 2000. Test of gross motor development: Examiner's manual, 2nd, Austin, TX: Pro-.  [Google Scholar]) as applied to Chinese children. The Test of Gross Motor Development-2 was administered to 626 Hong Kong Chinese children. The outlier test with standard scoring was utilized. After data screening, a total of 614 cases (N = 614) were used for further analysis. The two-factor structure of the Test of Gross Motor Development-2 was tested using confirmatory factor analysis with maximum likelihood estimation to compute parameter estimates and to select the appropriate item for each factor. The goodness-of-fit indices supported that the model was tenable (goodness-of-fit index = .95, root mean square error of approximation = .06, standardized root mean square residual = .04, comparative-fit index = .97). The findings of this study suggested that the two-factor structure proposed by Ulrich (2000 Ulrich, D. A. 2000. Test of gross motor development: Examiner's manual, 2nd, Austin, TX: Pro-.  [Google Scholar]) fit the data of Hong Kong Chinese children.  相似文献   

10.
The Trichotomous Achievement Goal Scale was developed by Agbuga and Xiang (2008 Agbuga, B. and Xiang, P. 2008. Achievement goals and their relations to self-reported persistence/effort in secondary physical education: A trichotomous achievement goal framework. Journal of Teaching in Physical Education, 27: 179191. [Web of Science ®] [Google Scholar]) by including selected items from the scales of Duda and Nicholls (1992 Duda, J. L. and Nicholls, J. 1992. Dimensions of achievement motivation in schoolwork and sport. Journal of Educational Psychology, 84: 290299. [Crossref], [Web of Science ®] [Google Scholar]), Elliot (1999 Elliot, A. J. 1999. Approach and avoidance motivation and achievement goals. Educational Psychologist, 34: 169189. [Taylor & Francis Online], [Web of Science ®] [Google Scholar]), and Elliot and Church (1997 Elliot, A. J. and Church, M. A. 1997. A hierarchical model of approach and avoidance achievement motivation. Journal of Personality and Social Psychology, 72: 218232. [Crossref], [Web of Science ®] [Google Scholar]) 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 Fornell, C. and Larcker, D. F. 1981. Evaluating structural equation models with unobservable variables and measurement error. Journal of Marketing Research, 18: 3950. [Crossref], [Web of Science ®] [Google Scholar]) 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   

11.
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 Scandura, T. A. and Graen, G. B. 1984. Moderating effects of initial leader–member exchange status on the effects of a leadership intervention. Journal of Applied Psychology, 69: 428436. [Crossref], [Web of Science ®] [Google Scholar]) to measure leader (coach)–member (player) exchange and Pines's (2005 Pines, A. M. 2005. The burnout measure, short version. International Journal of Stress Management, 12: 7888. [Crossref] [Google Scholar]) abbreviated version of the burnout scale developed by Pines and Aronson (1988 Pines, A. M. and Aronson, E. 1988. Career bumout: Causes and cures, New York: Free Press.  [Google Scholar]) 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   

12.
In the time between its founding and the fall of the wall in November 1989, more than three million people left the German Democratic Republic, many of them illegally and under dangerous circumstances. The party leadership perceived this mass exodus of its citizens as one of the major threats for the real socialist regime.1?1. Bispinck Bispinck, Henrick. “Republikflucht. Flucht und Ausreise als Problem der DDR-Führung.” Vor dem Mauerbau. Politik und Gesellschaft der DDR in den Fünfziger Jahren, edited by MichaelSchwartz and Hermann Wentker, 285309. München: Oldenbourg Wissenschaftsverlag, 2003. [Google Scholar], “Republikflucht.”‘Republikflucht’, as this move from East to West was called by the party leadership, was the reason for the two most important hiatuses in Eastern German history: the first result was that the SED leadership built the wall in August 1961. Many years later, in the fall of 1989, the situation culminated, when a flood of desperate refugees tried to escape to the Federal Republic of Germany via Hungary, Poland and Czechoslovakia, thus effectively hurrying along the regime's demise. The world of sports, too, was considerably affected by this phenomenon. The following essay shall offer a short historical summary of the different reasons and routes Eastern German top athletes chose for their escape. Examples from various decades show that in spite of individual circumstances certain similarities in pattern can be made out, especially in respect to the way the government dealt with these cases of ‘treason’.  相似文献   

13.
14.
Abstract

A scale has recently been developed to measure moral disengagement in sport (Boardley & Kavussanu, 2007 Boardley, I. D. and Kavussanu, M. 2007. Development and validation of the Moral Disengagement in Sport Scale. Journal of Sport & Exercise Psychology, 29: 608628. [PubMed], [Web of Science ®] [Google Scholar]). It consists of 32 items that measure the eight mechanisms of moral disengagement proposed by Bandura (1991 Bandura, A. 1991. “Social cognitive theory of moral thought and action”. In Handbook of moral behaviour and development: Theory, research, and applications, Edited by: Kurtines, W. M. and Gewirtz, J. L. Vol. 1, 71129. Hillsdale, NJ: Lawrence Erlbaum Associates.  [Google Scholar]). In the present study, we aimed to: (a) examine whether a subset of these items could form a short version of the scale; (b) provide evidence for the construct validity of the short version; and (c) test its measurement invariance across sex and sport type. A total of 992 football, rugby, hockey, basketball, and netball players from three different samples completed the long version of the scale. Data analyses indicated that the short version of the scale consisted of eight items and had high internal consistency. Construct validity of the scale was evidenced via correlations with sport moral disengagement and prosocial and antisocial behaviour. Multisample confirmatory factor analyses established measurement invariance across sex and partial measurement invariance across four team sports. In conclusion, the short version of the scale is a reliable and valid measure of moral disengagement in sport.  相似文献   

15.
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 Costa, P. T. and McCrae, R. R. 1992. Revised NEO personality inventory and NEO five-factor inventory: Professional manual, Odessa, FL: Psychological Assessment Resources.  [Google Scholar]), and the Coping Function Questionnaire for Sport (Kowalski & Crocker, 2001 Kowalski, K. C. and Crocker, P. R. E. 2001. Development and validation of the Coping Function Questionnaire for adolescents in sport. Journal of Sport and Exercise Psychology, 23: 136155. [Web of Science ®] [Google Scholar]). 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   

16.
Abstract

Confidence has been one of the most consistent factors in distinguishing the successful from the unsuccessful athletes (Gould, Weiss, & Weinberg, 1981 Gould, D., Weiss, M. and Weinberg, R. 1981. Psychological characteristics of successful and non-successful Big Ten wrestlers. Journal of Sport Psychology, 3: 6981.  [Google Scholar]) and Bandura (1997 Bandura, A. 1997. Self-efficacy. The exercise of control, New York: W. H. Freeman.  [Google Scholar]) proposed that imagery is one way to enhance confidence. Therefore, the purpose of the present study was to examine the relationship between imagery use and confidence in soccer (football) players. The participants included 122 male and female soccer athletes ages 11–14 years participating in both house/recreation (n = 72) and travel/competitive (n = 50) levels. Athletes completed three questionnaires; one measuring the frequency of imagery use, one assessing generalised self-confidence, and one assessing self-efficacy in soccer. A series of regression analyses found that Motivational General-Mastery (MG-M) imagery was a signifant predictor of self-confidence and self-efficacy in both recreational and competitive youth soccer players. More specifically, MG-M imagery accounted for between 40 and 57% of the variance for both self-confidence and self-efficacy with two other functions (MG-A and MS) contributing marginally in the self-confidence regression for recreational athletes. These findings suggest that if a youth athlete, regardless of competitive level, wants to increase his/her self-confidence or self-efficacy through the use of imagery, the MG-M function should be emphasised.  相似文献   

17.
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 Zimmerman, B. J. 1989. A social cognitive view of self-regulated academic learning. Journal of Educational Psychology, 81: 329339. [Crossref], [Web of Science ®] [Google Scholar], 2006 Zimmerman, B. J. 2006. “Development and adaptation of expertise: The role of self-regulatory processes and beliefs”. In The Cambridge handbook of expertise and expert performance, Edited by: Ericsson, K. A., Charness, N., Feltovich, P. J. and Hoffman, R. R. 705722. New York: Cambridge University Press. [Crossref] [Google Scholar]). 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   

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The area of competitive anxiety continues to be extensively researched with considerable attention focused on the notion of ‘direction’. The purpose of this review is to demonstrate how the study of direction has advanced our understanding of the competitive anxiety response through providing an overview of the existing research, and emphasizing why sport psychologists investigated the underlying mechanisms of performers’ facilitative interpretations of anxiety symptoms. Finally, we discuss how direction has been integrated into Lazarus (1990 Lazarus, R.S. 1990. Theory-based stress measurement. Psychological Inquiry, 1: 313. [Taylor & Francis Online] [Google Scholar], 1991a Lazarus, R.S. 1991a. Emotion and adaptation, New York: Oxford University Press.  [Google Scholar]); Lazarus & Folkman, 1984) transactional perspective of stress, and how this may be used to inform future research into the broader area of competition stress.  相似文献   

20.
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 Bar-Eli, M. and Tenenbaum, G. 1989a. A theory of individual psychological crisis in competitive sport. Applied Psychology, 38: 107120. [Crossref], [Web of Science ®] [Google Scholar]). 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 Apter, M. J. 1982. The experience of motivation: The theory of psychological reversals, London: Academic Press.  [Google Scholar]) and self-monitoring and distraction theories (Baumeister, 1984 Baumeister, R. F. and Steinhilber, A. 1984. Paradoxical effects of supportive audiences on performance under pressure: The home field disadvantage in sports championships. Journal of Personality and Social Psychology, 47: 8593. [Crossref], [Web of Science ®] [Google Scholar]) be included in the design of future investigations pertaining to choking under pressure.  相似文献   

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