Brain activation associated with motor imagery of coordination exercises and social abilities     

《European Journal of Sport Science》2013,13(7):671-677

Abstract

The purposes of the present study were: (1) to investigate the brain activation associated with coordination exercises done by one person and those by two persons and (2) to examine the interrelationships between the brain activation and social abilities. We were interested in testing the hypothesis that viewing two-person coordination exercises evokes more sophisticated brain activation than viewing one-person coordination exercises. Thirty Japanese college students served as subjects. There were two sessions in this study: the functional magnetic resonance imaging (fMRI) session and the social ability session. In the fMRI session, the subjects were instructed to imagine they were performing coordination exercises. Also, we examined the social abilities from the viewpoint of empathising. Empathising was measured by self-reports on the Systemising, Empathy and Autism Spectrum Quotients (SQ, EQ and AQ). Regarding brain activation, blood oxygenation level dependent (BOLD) activation was significant in specific areas such as the left cuneus (Brodmann area: BA 17) when the subjects imagined they were performing exercises involving two persons, as compared with the cases when they imagined they were performing exercises involving only one person. The fMRI results showed that exercises done by two persons require more sophisticated communication than those done by one person. Furthermore, the results of this study suggested that those with more autistic traits may undergo difficulties in the exercises done by two persons, especially in the case of playing a role as a follower.  相似文献   

Trends and knowledge base in sport and exercise psychology research: a bibliometric review study     

《International review of sport and exercise psychology》2013,6(1):71-94

Bibliometric methods were used to examine: (1) research themes in sport and exercise psychology articles published between 2008 and 2011; and (2) the intellectual base of the field of sport and exercise psychology, defined as influential literature being cited in these articles. The dataset consisted of 795 articles from five sport and exercise psychology journals and 345 articles obtained through citation-based extension (n = 1140 articles). A cluster analysis yielded 73 clusters showing themes in sport and exercise psychology research. Principal component analysis was used to identify and analyze relationships between 14 highly cited research areas constituting the intellectual base of sport and exercise psychology. Some main findings were: (1) the identification of many re-emerging themes, (2) research related to motivation seems to be extensive, (3) sport psychology and exercise psychology research share theoretical frameworks to some extent, however (4) differences compared to previous reviews indicate that sport psychology and exercise psychology may be regarded as two distinct research fields, rather than one united field, and (5) isolated research areas were identified indicating potential for research integration. Suggestions for future research are provided. The bibliometric approach presented a broad overview of trends and knowledge base in sport and exercise psychology research.  相似文献   

Attentional focus in endurance activity: new paradigms and future directions     

《International review of sport and exercise psychology》2013,6(1):106-134

After more than 35 years of investigation, research on attentional focus in endurance activity is still mired by a lack of consensus. Specific challenges relate to the conceptualisation of association and dissociation, and discrepancies in methodology, research design, and data collection techniques. This review addresses previously unresolved issues that may limit research findings in this field. Initial concerns include how the endpoint of exercise tasks is defined, how pace is controlled, and the subjects employed within research investigations. An additional objective is to provide direction for future investigations. Traditional views of attentional focus may be limited in their explanatory value. We present a new working model of attentional focus in endurance activity that may more precisely categorise cognitive processes. Finally, research on this topic needs to be grounded in a recognised framework that captures the dynamic nature of human cognition. We propose that existing perspectives are recognised, such as the parallel processing model of pain and the mindfulness approach, and in addition we propose a metacognitive perspective be explored. Means of integrating these conceptual frameworks are suggested to further enhance the understanding of attentional processes in endurance activity.  相似文献   

Reliability and validity of the German language version of Girls' Disinclination for Physical Activity Scale     

《European Journal of Sport Science》2013,13(7):711-719

Abstract

The high prevalence of insufficient physical activity (PA) among adolescents is an important public health issue. Studying reasons for disliking PA might help researchers better understand its underlying mechanisms, yet this psychological construct has been understudied. This study established the psychometric properties of the German language version of the Girls' Disinclination for Physical Activity Scale (G-DAS-Ger). Data were collected on a sample of 257 adolescent girls in Austria (mean age: 13.0 ± 0.7 years) using the G-DAS-Ger and the Physical Activity Enjoyment Scale. One week after the first assessment, the questionnaires were re-administered to 78 girls. Between two administrations, PA of 215 girls was monitored for seven consecutive days using the ActiGraph GT3X+ accelerometers. Confirmatory factor analysis of G-DAS-Ger showed good fit for a three-factor model (χ²/df = 2.025; Bollen–Stine (B-S) p = 0.159; root mean square error of approximation = 0.063; standardised root mean square residual = 0.054; comparative fit index = 0.950). Cronbach's alphas for G-DAS-Ger factors/subscales ranged 0.64–0.76. The test–retest reliability assessed by Spearman's rank correlation ranged 0.62–0.75. Only one subscale correlated significantly with vigorous-intensity PA (Spearman's rho = ?0.16) and none with moderate-to-vigorous-intensity PA, which indicated poor predictive validity of the G-DAS-Ger. Correlations between G-DAS-Ger subscales and enjoyment of PA ranged from ?0.29 to ?0.41, indicating satisfactory convergent validity. The G-DAS-Ger may be used in its present form to assess disinclination for PA among adolescent girls in German-speaking countries. However, our results put into question the stability of the originally proposed factor structure of the questionnaire and its predictive validity among German-speaking adolescent girls. Methodological refinements to the G-DAS-Ger may be required to improve its psychometric properties in this population.  相似文献   

Match activities of top-class female soccer assistant referees in relation to the offside line     

《European Journal of Sport Science》2013,13(6):371-376

Abstract

The aim of this study was to examine the match activities of top-class female assistant referees (mean age 34.8 years, s=3.5; stature 1.64 m, s=0.05; weight 58.1 kg, s=7.4; body mass index 21.6 kg · m^–2, s=2.4) in relation to the offside line. Computerized match analyses were performed on 14 top-class assistant referees during 10 matches (a total of 20 observations) from the 2006 Fédération Internationale de Football Association (FIFA) under-20 Women's World Championship held in Russia. In addition, the position of the second last defensive player of both teams was calculated throughout the matches to determine the distance from the assistant referee to the offside line. The total distance covered during a game was 5594 m (s=473), of which 27% was sideways movements (1492 m, s=135). High-intensity activities (>13 km · h^–1) accounted for 1999 m (s=371). Mean distance from the offside line during the entire match was 1.06 m (s=0.26). Total distance covered, high-intensity activities, and distance from the offside line were not different (P>0.05) between the two halves of the game or consecutive 15-min match periods. Our results show that: (1) the kinematic demands placed on top-class female assistant referees are similar to those of top-class male assistant refereeing except for the amount of high-intensity activities, and (2) assistant referees were able to maintain the distance from the offside line during the match, which suggests an ability to keep up with the pace of the play throughout the match.  相似文献   

Caffeine and resistance exercise: the effects of two caffeine doses and the influence of individual perception of caffeine     

《European Journal of Sport Science》2013,13(10):1342-1348

Abstract

Although caffeine is a widely used ergogenic resource, some information regarding its effects on resistance exercises is still lacking. The objective of the present study was to verify the acute effect of the ingestion of two different doses of caffeine on performance during a session of resistance exercises and to analyze the perception of the subjects in relation to the intake of caffeine. Following a double-blind, randomised, cross-over, controlled, and non-placebo design, 14 trained and healthy men (24.7?±?6.8 years; 79.8?±?9.8?kg; 177.3?±?8.5?cm) performed a training session in chest-press, shoulder-press, and biceps curl exercises (3 sets until exhaustion; 70% 1RM; 3 min rest interval; 2?s for each concentric and eccentric phase) on three non-consecutive days after ingestion of 3?mg.kg^?1 caffeine (CAF3), 6?mg.kg^?1 caffeine (CAF6), or no substance (CON). Subjects were informed that one of the caffeine doses would be placebo. The total number of repetitions performed in CON (93.6?±?22.4) was significantly lower than in CAF3 (108.0?±?19.9, P?=?0.02) and in CAF6 (109.3?±?19.8, P?=?0.03) and there were no differences between caffeine doses. Eight subjects noticed that caffeine was in CAF3 and six in CAF6 and there were no differences in the number of repetitions between sessions in which the subjects perceived and did not perceive caffeine. In conclusion, caffeine doses of 3 or 6?mg.kg^?1 similarly increased performance in resistance upper limb exercises, independent of the subject's perception of substance ingestion.  相似文献   

International conference on sport,leisure and ergonomics     

Jody Lynn Virr  Alex Game  Gordon John Bell 《Journal of sports sciences》2013,31(3):239-258

Abstract

The aim of this study was to determine the physical demands of women’s rugby union match play using time–motion analysis and heart rate (HR) response. Thirty-eight premier club level female rugby players, ages 18–34 years were videotaped and HRs monitored for a full match. Performances were coded into 12 different movement categories: 5 speeds of locomotion (standing, walking, jogging, striding, sprinting), 4 forms of intensive non-running exertion (ruck/maul/tackle, pack down, scrum, lift) and 3 discrete activities (kick, jump, open field tackle). The main results revealed that backs spend significantly more time sprinting and walking whereas forwards spend more time in intensive non-running exertion and jogging. Forwards also had a significantly higher total work frequency compared to the backs, but a higher total rest frequency compared to the backs. In terms of HR responses, forwards displayed higher mean HRs throughout the match and more time above 80% of their maximum HR than backs. In summary, women’s rugby union is characterised by intermittent bursts of high-intensity activity, where forwards and backs have similar anaerobic energy demands, but different specific match demands.  相似文献   

The effect of an intermittent,high-intensity warm-up on supramaximal kayak ergometer performance     

DAVID BISHOP  DARREL BONETTI  MATTHEW SPENCER 《Journal of sports sciences》2013,31(1):13-20

It has previously been shown that the metabolic acidaemia induced by a continuous warm-up at the 'lactate threshold' is associated with a reduced accumulated oxygen deficit and decreased supramaximal performance. The aim of this study was to determine if an intermittent, high-intensity warm-up could increase oxygen uptake (V02) without reducing the accumulated oxygen deficit, and thus improve supramaximal performance. Seven male 500 m kayak paddlers, who had represented their state, volunteered for this study. Each performed a graded exercise test to determine V02max and threshold parameters. On subsequent days and in a random, counterbalanced order, the participants then performed a continuous or intermittent, high-intensity warm-up followed by a 2 min, all-out kayak ergometer test. The continuous warm-up consisted of 15 min of exercise at approximately 65% V02max. The intermittent, high-intensity warm-up was similar, except that the last 5 min was replaced with five 10 s sprints at 200% V02max, separated by 50 s of recovery at ~55% V02max. Significantly greater (P<0.05) peak power (intermittent vs continuous: 629 ± 199 vs 601 ± 204W) and average power (intermittent vs continuous: 328±39.0 vs 321 ±42.4 W) were recorded after the intermittent warm-up. There was no significant difference between conditions for peak V02, total V02 or the accumulated oxygen deficit. The results of this study indicate that 2 min all-out kayak ergometer performance is significantly better after an intermittent rather than a continuous warm-up.  相似文献   

Athens 2004: the pollution climate and athletic performance     

Geraint Florida-James  Ken Donaldson  Vicki Stone 《Journal of sports sciences》2013,31(10):967-980

Athens sits in a basin approximately 450 km² in area, surrounded by mountains and open sea. Anthropogenic emissions in conjunction with the topographical and meteorological conditions can result in high air pollution within the city. The pollutants of concern for athletes competing in Athens 2004 appear to be nitrogen dioxide (NO₂), ozone and particulate (PM₁₀) pollution. Exposure to elevated ozone concentrations has been reported to give rise to symptoms that include cough, chest pain, difficulty in breathing, headache, eye irritation and a decrease in forced expiratory volume in one second. All of these effects are likely to impact upon performance, and several studies of cyclists suggest this to be the case. In contrast, the impact of ambient concentrations of NO₂ appears to be negligible on normal activities, but at high exercise intensities the impact remains unclear. The use of currently available information and models to predict the effect of ozone and other pollutants on elite athletes is problematical, since such models are based upon significantly lower ventilation rates than those achieved by some elite athletes. In addition, it is already known that the response to ozone can vary somewhat between individuals. Since the individuals who will be competing in Athens are physiologically very different to the participants in most published studies, it is difficult to predict individual responses. There is some evidence to indicate that adaptation to the adverse health and performance effects of ozone can occur, so that performance is partially recovered on re-exposure. The adaptation is not seen in all studies and appears to be dependent on several factors, including the initial sensitivity of the individual to ozone. Antioxidant supplementation has also been shown in some studies to partially ameliorate the adverse effects of ozone by counteracting the oxidative stress mechanism associated with this pollutant. Whether this transfers to performance enhancement per se remains unclear at present. Additional research is required to gain a sound understanding of the effects of a complex mixed air pollution exposure on the pulmonary function and performance of athletes exercising at high work intensities.  相似文献   

Use of NSE/PS2m-transgenic mice in the study of the protective effect of exercise on Alzheimer's disease     

Jun Y Cho  Dae Y Hwang  Tae S Kang  Dong H Shin  Jin H Hwang  Chae H Lim 《Journal of sports sciences》2013,31(11):943-951

In its late stage, Alzheimer's disease results in progressive muscle weakness in the arms and legs. The aim of this study was to determine whether mice expressing the skeletal muscle-specific mutant PS2 gene (a model of Alzheimer's disease) are a useful experimental system to study the protective effect of exercise on Aβ-42 reduction, improvement of behavioural function and changes in metabolic parameters. With this aim in mind, the transgenic mice were subjected to treadmill exercise for 3 months. The results showed that in transgenic mice, but not in normal mice, treadmill exercise resulted in a reduction of Aβ-42 deposits and an improvement in behavioural function, thereby restoring normal concentrations of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglyceride. Thus, exercise may represent a practical therapeutic strategy for use with human patients with Alzheimer's disease.  相似文献