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951.
Why young elite athletes fear failure: consequences of failure   总被引:1,自引:0,他引:1  
Fear of failure can have negative effects on children in achievement settings, affecting many aspects of their lives. Perceiving the consequences of failure to be aversive provides the basis for fear of failure, and the anticipation of a threatening outcome elicits fear. Problems attributed to fear of failure in achievement settings are prevalent. Sport is a popular and significant achievement domain for children and adolescents and there is a lack of research on fear of failure in sport among this age group. Therefore, the aim of the present study was to investigate fear of failure in the sport domain among young elite athletes, and to explore their perceptions of the consequences of failure. Interviews were conducted individually with nine athletes aged 14 - 17 years (5 males, 4 females). Analysis identified and organized perceived consequences of failure into themes and categories. Results revealed that the most commonly perceived aversive consequences of failure were diminished perception of self, no sense of achievement, and the emotional cost of failure. These findings are consistent with those reported in adult population, suggesting the potential for generalizing existing results to young elite athletes.  相似文献   
952.
In the present study, we examined the performance environment of the England youth soccer teams. Using a semi-structured protocol with a prospective sample, national coaches (n = 6), sport scientists (n = 3), and players (n = 4) were interviewed directly following international tournaments about the factors that positively and negatively influenced performance. Qualitative content analysis revealed the following factors as major positive influences on performance: adhering to a consistent tournament strategy, player understanding, strong team cohesion, organized entertainment activities, detailed knowledge of opposition, an effective physical rest/recovery strategy, and previous tournament experience. Major factors perceived to have negatively influenced performance included: over-coaching, player boredom, player anxiety, physical superiority of the opposition, physical fatigue over the tournament, problems sleeping, and lack of information on the opposition. Eight overall dimensions emerged to describe the performance environment: planning and organization, physical environment, tactical factors, development and performance philosophy, psychological factors, physical factors, social factors, and coaching. The findings support recent work that suggests the performance environment is multifaceted, with performance being contingent upon a broad range of interacting factors that go beyond the traditional psychosocial and physical domains.  相似文献   
953.
The effect of altering the rest period on adaptations to high-repetition resistance training is not well known. Eighteen active females were matched according to leg strength and repeated-sprint ability and randomly allocated to one of two groups. One group performed resistance training with 20-s rest intervals between sets, while the other group employed 80-s rest intervals between sets. Both groups performed the same total training volume and load. Each group trained 3 days a week for 5 weeks [15- to 20-repetition maximum (RM), 2 - 5 sets]. Repeated-sprint ability (5x6-s maximal cycle sprints), 3-RM leg press strength, and anthropometry were determined before and after each training programme. There was a greater improvement in repeated-sprint ability after training with 20-s rest intervals (12.5%) than after training with 80-s rest intervals (5.4%) (P = 0.030). In contrast, there were greater improvements in strength after training with 80-s rest intervals (45.9%) than after training with 20-s rest intervals (19.6%) (P = 0.010). There were no changes in anthropometry for either group following training. These results suggest that when training volume and load are matched, despite a smaller increase in strength, 5 weeks of training with short rest periods results in greater improvements in repeated-sprint ability than the same training with long rest periods.  相似文献   
954.
We use prices realized for Picasso prints at auctions worldwide, as well as the 100 prints that comprise his Vollard Suite, to test the law of one price: the proposition that identical art objects sold contemporaneously should command the same price regardless of the auction house or geographic region where the sale takes place. Picasso is the most prolific printmaker of the twentieth century and, from 1977 to 2004, his prints appreciated in price significantly faster than the prints of modern masters as a whole. We find that Picasso prints sold in the United States command higher prices than in Europe. However, prices realized at Sotheby’s in New York are no longer higher than at Christie’s in New York, nor at Kornfeld than at other auction houses. We find evidence of “irrational exuberance” in the transitory nature of the extraordinary prices realized for the Picasso prints included in the 1997 sale of the collection of Victor and Sally Ganz at Christie’s in New York. More generally, we find substantial noise in auction outcomes, a result well known to savvy auction goers.
Pauline M. Shum (Corresponding author)Email:
  相似文献   
955.
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.  相似文献   
956.
This aim of this study was to compare the new Actigraph (GT1M) with the widely used Model 7164. Seven days of free-living physical activity were measured simultaneously using both the Model 7164 and GT1M in 30 Indian adolescents (mean age 15.8 years, s = 0.6). The GT1M was on average 9% lower per epoch than model 7164, thus a correction factor of 0.91 is suggested for comparison between the two monitors. The differences between monitors increased in magnitude with intensity of activity (P < 0.001) but remained randomly distributed (r = 0.01, P = 0.96). No significant difference was observed between monitors for time spent in moderate (P = 0.31) and vigorous (P = 0.34) physical activity when using the same epoch length. The Model 7164 classified less time as sedentary (P < 0.001) and more time as light-intensity activity (P < 0.001) than the GT1M. In conclusion, data from the GT1M can be compared with historical data using average counts per minute with a correction factor, and the two models might be comparable for assessing time spent in moderate to vigorous physical activity in children when using the same epoch length.  相似文献   
957.
Weight transfer research in the golf swing has produced conflicting and inconclusive results. A limitation of previous studies is the assumption that only one swing "style" exists within the golf swing. If different styles, or movement strategies, exist and if the different styles are analysed together in a single group, statistical errors will result. The aim of this study was to determine if different weight transfer styles exist in the golf swing by applying cluster analysis to centre of pressure (CP) patterns in the direction of hit (CPy) and to evaluate cluster analysis issues. Sixty-two professional to high handicap golfers performed simulated drives, hitting a golf ball into a net, while standing on two force plates. Centre of pressure position relative to the feet (CPy%) was quantified at eight swing events identified from 200-Hz video. Cluster analysis identified two major CPy% styles: a "Front Foot" style and a "Reverse" style. Both styles began with CPy% positioned evenly between the feet, moved to the back foot during backswing, and then forward during early downswing. Beyond early downswing, the Front Foot group continued to move CPy% to the Front Foot through to ball contact, while the Reverse group moved CPy% towards the back foot through ball contact and follow-through. Both weight transfer styles were evident across skill levels from professional to high handicap golfers, indicating that neither style was a technical error. Cluster analysis should include hierarchical and non-hierarchical clustering and use objective measures combined with theoretical assessment to determine the optimal number of clusters. Furthermore, a number of validation procedures should always be used to validate the solution.  相似文献   
958.
The study's purpose was to identify the mediating role of intention and the stages of change (SOC) in physical activity (PA) over a 6-month period using two models (theory of planned behavior [TPB] and TPB/SOC). Participants were 143 adults with physical disabilities (70.68% response rate; M age = 46.03). The TPB constructs, SOC (time 1), and PA (time 2) were assessed using standardized self-report questionnaires. Based on path analyses, attitude had the highest effect on intention and SOC followed by perceived behavioral control within both well-fit models. The variance in PA explained by the first (TPB) and second (TPB/SOC) models was 16% and 28% respectively. In the just identified model of TPB/SOC, the direct effect of SOC on physical activity remained strong (gamma(soc.pa) = .45) and SOC approached full mediation through attitude. Health promotion interventions need to include both intention and behavior elements (SOC) reinforcing increased PA value and barrier elimination.  相似文献   
959.
A common practice for counteracting response acquiescence in psychological measures has been to employ both negatively and positively worded items. However, previous research has highlighted that the reliability of measures can be affected by this practice (Spector, 1992). The purpose of the present study was to examine the effect that the presence of negatively worded items has on the internal reliability of the Group Environment Questionnaire (GEQ). Two samples (N = 276) were utilized, and participants were asked to complete the GEQ (original and revised) on separate occasions. Results demonstrated that the revised questionnaire (containing all positively worded items) had significantly higher Cronbach alpha values for three of the four dimensions of the GEQ. Implications, alternatives, and future directions are discussed.  相似文献   
960.
The aims of the study were to modify the training impulse (TRIMP) method of quantifying training load for use with intermittent team sports, and to examine the relationship between this modified TRIMP (TRIMP(MOD)) and changes in the physiological profile of team sport players during a competitive season. Eight male field hockey players, participating in the English Premier Division, took part in the study (mean+/-s: age 26+/-4 years, body mass 80.8+/-5.2 kg, stature 1.82+/-0.04 m). Participants performed three treadmill exercise tests at the start of the competitive season and mid-season: a submaximal test to establish the treadmill speed at a blood lactate concentration of 4 mmol . l(-1); a maximal incremental test to determine maximal oxygen uptake ([V]O(2max)) and peak running speed; and an all-out constant-load test to determine time to exhaustion. Heart rate was recorded during all training sessions and match-play, from which TRIMP(MOD) was calculated. Mean weekly TRIMP(MOD) was correlated with the change in [V]O(2max) and treadmill speed at a blood lactate concentration of 4 mmol x l(-1) from the start of to mid-season (P<0.05). The results suggest that TRIMP(MOD) is a means of quantifying training load in team sports and can be used to prescribe training for the maintenance or improvement of aerobic fitness during the competitive season.  相似文献   
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