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1.
The purpose of this study was to examine the effect of one bout and three intermittent bouts of short-duration, high-intensity running on the performance of a sports-specific psychomotor skill. Participants (N=13) were male soccer players (M age 20.5 yr., SD=2.0) who had been playing semi-professionally for M=2.1 years, SD=1.11 and trained twice a week. They undertook a soccer-passing test in three conditions: following rest, following a 100-m sprint and following 3 x 100-m sprints, with 30-sec. rest intervals between sprints. Passing accuracy showed a significant linear deterioration, while number of passes showed a significant quadratic effect. Low to moderate linear regression correlations were found between posttest heart rate and absolute and variable errors on the test. It was concluded that short-duration, high-intensity exercise has a negative effect on accuracy in a sports-specific task that requires both perceptual judgment and motor control.  相似文献   

2.
Two experiments evaluated the influence of attentional focus on 10-meter sprint time and start kinetics in a group of collegiate soccer players and highly experienced sprinters. In Experiment 1, the collegiate soccer players were asked to perform 10-meter sprints under an external focus condition, an internal focus condition and a control condition. For the 10-meter sprint time, the results showed that both the external focus and control conditions resulted in significantly faster sprint times than the internal focus condition. There were no significant differences observed between the external focus and control conditions. There were also no significant differences observed across any of the conditions for a select set of kinetic variables. In Experiment 2, the highly experienced sprinters performed the same 10-meter sprint task using the same instructional conditions as in Experiment 1. For the 10-meter sprint time and kinetic variables, there were no significant differences observed across any of the conditions. These results provide new evidence that experience level mediates the influence of attentional focus on sprint performance.  相似文献   

3.
Elite swimmers are individual athletes competing mostly on their own. However, when competing in a relay team, they are exposed to social influences possibly leading to effort gains compared to their individual performance. This study investigated effort gains in relay team members during 4 × 100 m freestyle races of Olympic Games and World Championships across the past 20 years. We assumed increasing effort gains in swimmers competing on later serial positions within their relay team since weaknesses in their performances can increasingly less be compensated by their teammates (social indispensability). Furthermore, we assumed a stronger gain in female athletes since females have been shown to be more affected by social indispensability then males. Using linear mixed modelling analyses, we additionally examined the moderating impact of the relay team outcome (i.e. medal-winning chance) on effort gains and indispensability effects while accounting for current team rankings at change-over. Except for the first swimmer, overall effort gains in relay performances were found as compared to performances in individual races during the same championship. Furthermore, these gains were close to equally distributed among both laps of the 100 m distance. However, even though effort gains are tending to be most pronounced for the last relay team swimmer we failed to detect any significant indispensability effect in our data set. Noteworthy, female swimmers showed larger effort gains when winning a medal (based on the current team rankings) was likely. In contrast, males showed effort gains irrespective of the serial order within the relay team and medal chance. Consequently, tentative recommendations are derived on how to line up a relay team.  相似文献   

4.
Physical performance and movement skills are differentiated by brain hemispheric dominance. Relations of handedness and footedness to differences in sprint speed and multiple sprints performances were investigated in 362 prepubertal, male, novice wrestlers. Participants with two months of irregular training experience were grouped by hand and foot preferences and matched on age and anthropometry. Mean running speed was associated with the number of sprints and handedness, but not with footedness. The decrease in sprint speed was less for right-handed subjects, who also had better sprinting speed and multiple sprint performance. Symmetrical arm and leg strength development for left-handers should be emphasized.  相似文献   

5.
Music has often been portrayed as a dissociative (i.e., distracting) mechanism. This study demonstrates that music may not be unifunctional in regards to attentional focus; that is, external concentration on music can coexist with task-relevant thoughts. Female intercollegiate rowers (N = 26) performed four 1,000 m sprints on a rowing ergometer at maximal effort under music, coxswain, combined music and coxswain, and control conditions. Findings indicate that during the 1,000 m rowing sprint, both external and task-relevant dimensions of attentional focus can exist simultaneously. This implies a new consideration of music as either dissociative or associative based on task-related factors.  相似文献   

6.
Swimming constraints and arm coordination   总被引:1,自引:0,他引:1  
Following Newell's concept of constraint (1986), we sought to identify the constraints (organismic, environmental and task) on front crawl performance, focusing on arm coordination adaptations over increasing race paces. Forty-two swimmers (15 elite men, 15 mid-level men and 12 elite women) performed seven self-paced swim trials (race paces: as if competitively swimming 1500m, 800m, 400m, 200m, 100m, 50m, and maximal velocity, respectively) using the front crawl stroke. The paces were race simulations over 25m to avoid fatigue effects. Swim velocity, stroke rate, stroke length, and various arm stroke phases were calculated from video analysis. Arm coordination was quantified in terms of an index of coordination (IdC) based on the lag time between the propulsive phases of each arm. This measure quantified three possible coordination modes in the front crawl: opposition (continuity between the two arm propulsions), catch-up (a time gap between the two arm propulsions) and superposition (an overlap of the two arm propulsions). With increasing race paces, swim velocity, stroke rate, and stroke length, the three groups showed a similar transition in arm coordination mode at the critical 200m pace, which separated the long- and mid-pace pattern from the sprint pace pattern. The 200m pace was also characterized by a stroke rate close to 40strokemin(-1). The finding that all three groups showed a similar adaptation of arm coordination suggested that race paces, swim velocity, stroke rate and stroke length reflect task constraints that can be manipulated as control parameters, with race paces (R(2)=.28) and stroke rate (R(2)=.36) being the best predictors of IdC changes. On the other hand, only the elite men reached a velocity greater than 1.8ms(-1) and a stroke rate of 50strokemin(-1). They did so using superposition of the propulsion phases of the two arms, which occurred because of the great forward resistance created when these swimmers achieved high velocity, i.e., an environmental constraint. Conversely, the elite women and mid-level men had shorter stroke lengths and maintained a time gap between the propulsions of the two arms throughout the increase in paces, with gender and expertise explaining 9% and 8.3% of the IdC changes, respectively. These results indicate that arm coordination cannot be interpreted solely from the IdC value but should be considered from the perspective of task, environmental, and organismic constraints. These constraints can serve as control parameters in experiments aimed at gaining insight into changes in arm coordination during the front crawl. In this context, catch-up coordination, which is often considered as a mistake, was seen to be an adaptation to a relative constraint.  相似文献   

7.
Willingness to date members of other races was examined among 200 men with same-sex dating preference (n = 100) and opposite-sex dating preference (n = 100), and 200 women with same-sex dating preference (n = 100) and opposite-sex dating preference (n = 100) who were randomly selected from an Internet dating web site. Overall, results indicated a greater willingness among gay participants than heterosexual participants to date people of other races. A 2 (Sex) x 2 (Sexual Orientation) analysis of variance showed an interaction, with lesbian women more willing to date other races than gay men, while among heterosexual participants men were more willing than women to date other races. The role of mate selection theory, and the importance of the status afforded various races in U.S. society, were applied to interpret people's willingness to date other races.  相似文献   

8.
Stride mechanical imbalances between the lower limbs may be detrimental to performance and/or increase injury risks. This study describes the time course and magnitude of asymmetries in running mechanical variables during repeated treadmill sprints and examines whether inter-limb differences in sprinting mechanics increase with fatigue. Thirteen non-injured male athletes performed five 5-s sprints with 25-s recovery on an instrumented treadmill, allowing the continuous (step-by-step) measurement of running kinetics/kinematics and spring-mass characteristics calculation. For each variable, bilateral leg asymmetry (BLA%) between the left and the right leg was defined as: {[(high value  low value)/low value] × 100}. BLA% for propulsive power and horizontal forces averaged ∼12–13%, while lower values occurred for step-averaged values of running velocity, resultant and vertical forces (all ∼4%). For all sprints, kinematic BLA% ranged from 1.6 ± 1.0% (swing time) to 9.0 ± 5.3% (aerial time). BLA% for vertical and leg stiffness was 6.4 ± 4.9% and 7.6 ± 3.6%, respectively. While distance covered decreased across repetitions (P < 0.05), there was no significant interaction between sprint repetitions and leg side for any of the mechanical variables studied (all P > 0.05). Although inter-limb differences were observed for many running kinetics/kinematics and spring-mass characteristics during repeated treadmill sprints, the lack of interaction between sprint repetitions and leg side suggests that lower limbs fatigued at a similar rate.  相似文献   

9.
Early in the first year of life infants exhibit equivalent performance distinguishing among people within their own race and within other races. However, with development and experience, their face recognition skills become tuned to groups of people they interact with the most. This developmental tuning is hypothesized to be the origin of adult face processing biases including the other-race bias. In adults the other-race bias has also been associated with impairments in facial emotion processing for other-race faces. The present investigation aimed to show perceptual narrowing for other-race faces during infancy and to determine whether the race of a face influences infants' ability to match emotional sounds with emotional facial expressions. Behavioral (visual-paired comparison; VPC) and electrophysiological (event-related potentials; ERPs) measures were recorded in 5-month-old and 9-month-old infants. Behaviorally, 5-month-olds distinguished faces within their own race and within another race, whereas 9-month-olds only distinguish faces within their own race. ERPs were recorded while an emotion sound (laughing or crying) was presented prior to viewing an image of a static African American or Caucasian face expressing either a happy or a sad emotion. Consistent with behavioral findings, ERPs revealed race-specific perceptual processing of faces and emotion/sound face congruency at 9 months but not 5 months of age. In addition, from 5 to 9 months, the neural networks activated for sound/face congruency were found to shift from an anterior ERP component (Nc) related to attention to posterior ERP components (N290, P400) related to perception.  相似文献   

10.
In 169 male 100-km ultra-marathoners, the variables of anthropometry, training, and prerace experience, in order to predict race time, were investigated. In the bivariate analysis, age (r = .24), body mass (r = .20), Body Mass Index (r = .29), circumference of upper arm (r = .26), percent body fat (r = .45), mean weekly running hours (r = -.21), mean weekly running kilometers (r = -.43), mean speed in training (r=-.56), personal best time in a marathon (r = .65), the number of finished 100-km ultra-runs (r = .24), and the personal best time in a 100-km ultra-run (r = .72) were associated with race time. Stepwise multiple regression showed that training speed (p < .0001), mean weekly running kilometers (p < .0001), and age (p < .0001) were the best correlations for a 100-km race time. Performance may be predicted (n=169, r2 = .43) by the following equation: 100-km race time (min) = 1085.60 - 36.26 x (training speed, km/hr.) - 1.43 x (training volume, km/wk.) + 2.50 x (age, yr.). Overall, intensity of training might be more important for a successful outcome in a 100-km race than anthropometric attributes. Motivation to train intensely for such an ultra-endurance run should be explored as this might be the key for a successful finish.  相似文献   

11.
Electromyographic reaction times (EMG-RTs) of the right biceps brachii muscle were examined for two movement patterns, elbow flexion and forearm supination, in 8 healthy male subjects under simple and complex RT conditions with varied preparatory intervals (PIs): 0, 200, 400, 600, and 800 msec. In the simple RT condition, the subject was informed of the movement patterns to be performed prior to beginning the trials. In the complex RT condition the subject had to choose one of the two movement patterns at the time of the presentation of a warning signal. The results indicated that: (1) compared with the simple RT condition a delay of about 100 msec. in over-all mean EMG-RT was observed at PI = 0 msec. in the complex RT condition; (2) the difference of over-all mean EMG-RT between the two RT conditions disappeared when PI = 400 msec.; and (3) the difference in EMG-RTs between flexion and supination in the complex RT condition became the same as that in the simple RT condition when PI = 700 msec. It is assumed that the preparatory set for response movements is organized in an order, resulting in the differentiation of RT.  相似文献   

12.
Fifty-three patrons of a harness racing track completed two measures of explanatory style prior to an afternoon's races. One measure assessed general explanatory style, using bad events taken from the Attributional Style Questionnaire, and the other measure assessed betting-specific explanatory style, using bad events specific to harness race betting. Subjects then kept a diary during the first eight races. After each race, they reported how much they had bet, whether they had won or lost, the major cause of the outcome, their confidence about winning future bets, and whether they were ruminating about past or future races. Explanatory style assessed in both ways had similar correlates. Explanatory style predicted the specific attributions made by subjects for losses. Pessimistic explanatory style (internal + stable + global attributions) predicted rumination following a lost bet, but it was unrelated to expressed confidence. Rumination after a loss was in turn associated with larger wagers on subsequent races and a tendency toward less successful wagers. These results clarify one way in which pessimistic explanatory style results in helplessness, and suggest a path by which problematic gambling may develop.  相似文献   

13.
Spatial-temporal parameters (velocity, stroke rate, stroke length) and arm-leg coordination in the butterfly stroke were studied as a function of race pace, skill (due to technical level, age, and experience) and gender. Forty swimmers (ten elite men, ten elite women, ten less-skilled men, and ten less-skilled women) performed the butterfly stroke at four velocities corresponding to the appropriate paces for the 400-m, 200-m, 100-m, and 50-m, respectively. Arm and leg stroke phases were identified by video analysis and used to calculate four time gaps (T1: the time difference between the start of the arms' catch phase and the start of the legs' downward phase of the first leg kick; T2: the time difference between the start of the arms' pull phase and the start of the legs' upward phase of the first leg kick; T3: the time difference between the start of the arms' push phase and the start of the legs' downward phase of the second leg kick; and T4: the time difference between the start of the arms' recovery and the start of the legs' upward phase of the second leg kick) and the total time gap (TTG), i.e., the sum of the four discrete time gaps. These values described the changing coupling of arm to leg actions over an entire stroke cycle. A significant race pace effect indicated that the synchronization between the key motor points of the arms and legs, which determine the starts and ends of the arm and leg stroke phases, increased with pace for all participants. A significant skill effect indicated that the elite swimmers had greater velocity, stroke length, and stroke rate and stronger synchronization of the arm and leg stroke phases than the less-skilled swimmers, due to smaller T2 and T3 and greater T1. A significant gender effect revealed greater velocity and stroke length for the men, and smaller T1 for the less-skilled women. These time gap differences between skill levels were related to the capacity of elite swimmers to assume a more streamlined position of trunk, head and upper limbs during leg actions, adopt a shorter glide and higher stroke rate to overcome great forward resistance, and generate higher forces and use better technique during the arm pull. Thus, coaches are advised to begin monitoring arm-leg coordination earlier in swimmers' careers to ensure that they attain their highest possible skill levels.  相似文献   

14.
听觉呈现条件下汉语双字词语义和语音启动的ERP研究   总被引:3,自引:1,他引:2  
在词汇决定实验中研究语义启动和语音启动,材料为通过听觉呈现的汉语双字词组成的词对(间隔600ms),记录行为数据和ERP数据,结果发现:(1)启动词与目标词之间的语义联系可显著改善对目标词的加工,表现为错误率降低、反应时缩短,以及N400波幅降低;(2)启动词与目标词之间的语音一致对目标词的加工既有干扰作用,又有促进作用。表现为错误率提高,但反应时趋向缩短,N400波幅亦呈下降趋势;(3)启动词与目标词首音相同比尾音相同有更大的干扰作用。  相似文献   

15.
This study aimed to assess the stability of the performance, pace and turn parameters of elite long-distance male swimmers during an 800 m freestyle race. The sample was composed by 38 male swimmers, participating in the 800 m event at the 2016 LEN European Aquatic Championships (long course meter). The performance, and a set of pace and turn parameters were analyzed. A customized software was used to perform each race analysis. Swimmers spent 64.05 ± 0.50% and 35.95 ± 0.49% of the final race time in the clean swim and turns, respectively. In the pace parameters, the clean swim was the only one that did not differ between the first and second half of the race (1.63 ± 0.05 vs 1.62 ± 0.05 m·s−1), and in the turn parameters, the water break distance was also similar (5.13 ± 1.17 vs 5.06 ± 0.98 m). A significant and moderate-strong variation was verified for the performance (total race lap effect: p < 0.001, η2 = 0.62), and a significant and moderate variation for the pace parameters (total race: p < 0.001, 0.15 ≤ η2 ≤ 0.33), and for the turn parameters (total race: p < 0.01, 0.15 ≤ η2 ≤ 0.33). Present data (pace and turn variation) shows that elite long-distance male swimmers do not maintain a similar pattern during an 800 m freestyle race. Future research is need to understand if this lack of pace and turn stability is the best way to enhance the performance, or if swimmers should be advised to control their pace and turn. Nevertheless, coaches are advised to help swimmers with feedback about their pace (i.e., controlling the intermediate 30 m) and turn performances (i.e., controlling the 5 m in and 15 m out), leading to a positive effect in their final race time.  相似文献   

16.
ABSTRACT

Participants in the study were 404 recreational runners. At the end of each week for three months they used an online diary to describe their psychological well-being for the week (a total of 4046 weeks), and they indicated if they had participated in an organized race each week (a total of 1111 races). Multilevel modeling analyses (weeks nested within persons) found that well-being, defined in terms of self-esteem, self-efficacy, life satisfaction, positive affect, and depressed affect, was higher during weeks in which participants had run in an organized race than it was during weeks in which they had not run in an organized race. Moreover, well-being was positively related to self-evaluations of performance in races. For recreational runners, finishing an organized race may represent the achievement of a goal, an achievement that increases well-being and may help maintain or increase the motivation to keep running.  相似文献   

17.
Ultra-endurance events test the adaptation of human physiology to extreme physical and mental demands, high levels of training, motivation, and physical conditioning among participants. To understand basic differences among participants according to the severity of the race, participants in qualifying events for two ultra-endurance cycling races, differing in length and intensity, were compared on measures of anthropometry, training, and support. One race was four times longer, required supporting teams, and racers typically had little sleep, which should lead to the qualifiers being substantially more highly trained than those from the shorter race. The qualifiers in the longer race had greater intensity in training while the qualifiers in the shorter race relied more on training volume. Different strategies and types of training reflected the different demands of the races. Future studies should evaluate personality and motivational differences in ultra-endurance events and between these athletes and athletes in other sports.  相似文献   

18.
19.
Two competing theories explain the other-‘race’ effect (ORE) either by greater perceptual expertise to same-‘race’ (SR) faces or by social categorization of other-‘race’ (OR) faces at the expense of individuation. To assess expertise and categorization contributions to the ORE, a promising—yet overlooked—approach is comparing activations for different other-‘races’. We present a label-based systematic review of neuroimaging studies reporting increased activity in response to OR faces (African, Caucasian, or Asian) when compared with the SR of participants. Hypothetically, while common activations would reflect general aspects of OR perception, ‘race’-preferential ones would represent effects of ‘race’-specific visual appearance. We find that several studies report activation of occipito-temporal and midcingulate areas in response to faces across different other-‘races’, presumably due to high demand on the visual system and category processing. Another area reported in response to all OR faces, the caudate nucleus, suggests the involvement of socio-affective processes and behavioural regulation. Overall, our results support hybrid models—both expertise and social categorization contribute to the ORE, but they provide little evidence for reduced motivation to process OR faces. Additionally, we identify areas preferentially responding to specific OR faces, reflecting effects of visual appearance.  相似文献   

20.
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