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1.
Abstract

The objective of this study was to determine whether sprint performance is related to the mechanical (elongation – force relationship of the tendon and aponeurosis, muscle strength) and morphological (fascicle length, pennation angle, muscle thickness) properties of the quadriceps femoris and triceps surae muscle – tendon units. Two groups of sprinters (slow, n = 11; fast, n = 17) performed maximal isometric knee extension and plantar flexion contractions on a dynamometer at 11 different muscle – tendon unit lengths. Elongation of the tendon and aponeurosis of the gastrocnemius medialis and the vastus lateralis was measured using ultrasonography. We observed no significant differences in maximal joint moments at the ankle and knee joints or morphological properties of the gastrocnemius medialis and vastus lateralis between groups (P > 0.05). The fast group exhibited greater elongation of the vastus lateralis tendon and aponeurosis at a given tendon force, and greater maximal elongation of the vastus lateralis tendon and aponeurosis during maximum voluntary contraction (P < 0.05). Furthermore, maximal elongation of the vastus lateralis tendon and aponeurosis showed a significant correlation with 100-m sprint times (r = ?0.567, P = 0.003). For the elongation – force relationship at the gastrocnemius medialis tendon and aponeurosis, the two groups recorded similar values. It is suggested that the greater elongation of the vastus lateralis tendon and aponeurosis of the fast group benefits energy storage and return as well as the shortening velocity of the muscle – tendon unit.  相似文献   

2.
Abstract

In this study, we examined the effect of two creatine monohydrate supplementation regimes on 24-h urinary creatine and methylamine excretion. Nine male participants completed two trials, separated by 6 weeks. Participants ingested 4 × 5 g · day?1 creatine monohydrate for 5 days in one trial and 20 × 1 g · day?1 for 5 days in the other. We collected 24-h urine samples on 2 baseline days (days 1–2), during 5 days of supplementation (days 3–7), and for 2 days post-supplementation (days 8–9). Urine was assayed for creatine using high-performance liquid chromatography and methylamine using gas chromatography. Less creatine was excreted following the 20 × 1 g · day?1 regime (49.25 ± 10.53 g) than the 4 × 5 g · day?1 regime (62.32 ± 9.36 g) (mean ± s; P < 0.05). Mean total excretion of methylamine (n = 6) over days 3–7 was 8.61 ± 7.58 mg and 24.81 ± 25.76 mg on the 20 × 1 g · day?1 and 4 × 5 g · day?1 regimes, respectively (P < 0.05). The lower excretion of creatine using 20 × 1 g · day?1 doses suggests a greater retention in the body and most probably in the muscle. Lower and more frequent doses of creatine monohydrate appear to further attenuate formation of methylamine.  相似文献   

3.
ABSTRACT

Digital technologies are now considered important in shaping young people's engagement in and with health and physical activity. Recent discussions show that the use of digital technologies to track health and fitness may over-emphasize the linear understanding of the body and health generally underpinned by Western health ideologies such as healthism. Other studies have shown the increased use of digital technologies in teaching Health and Physical Education (HPE) and as a means to enhance health and increase physical activity. Despite the opportunities and risks apparent in these studies, little is known about how HPE students make choices, negotiate, and resist or embrace the digitalisation of physical activity, exercise, and more broadly health. This study examines HPE students’ meaning making of risk and surveillance associated with the self-digitisation of exercise. The study further investigates how the concept of ‘prosumption’; the production, curation and consumption of self-data within the context of digitised health and physical activity, is understood. Based on the findings, we have constructed a typology of prosumers that can be used as a pedagogical device to illustrate the various kinds of subject positions students take up with digital technology in health and physical activity. This study extends the current understanding of prosumers by identifying the ‘ambivalent prosumer’. The results provide insights that have direct pedagogical implications in HPE teacher education specifically in the areas of knowledge production and consumption of knowledge through digital technology in health and physical activity.  相似文献   

4.
Current problems of health - related fitness promotion in children and adolescents- economic, social, cultural and other environmental factors. A relationship between the environment and the child, beginning dining the gestation period that influences both positive and negative, health outcomes later in life.[第一段]  相似文献   

5.
Abstract

The aims of the present study were to assess the maximal oxygen uptake and body composition of adult Chinese men and women, and to determine how these variables relate to age. The cross-sectional sample consisted of 196 men and 221 women aged 20 – 64 years. Maximal oxygen uptake ([Vdot]O2max) was determined by indirect calorimetry during a maximal exercise test on an electrically braked cycle ergometer. The correlations between [Vdot]O2max and fat mass were ?0.52 in men and ?0.58 in women. Linear regression defined the cross-sectional age-related decline in [Vdot]O2max as 0.35 ml · kg?1 · min?1 · year?1 in men and 0.30 ml · kg?1 · min?1 · year?1 in women. Multiple regression analysis showed that more than 50% of this cross-sectional decline in [Vdot]O2max was due to fat mass, lean mass, and age. Adding fat mass and lean mass to the multiple regression models reduced the age regression mass from 0.35 to 0.24 ml · kg?1 · min?1 · year?1 in men and from 0.30 to 0.15 ml · kg?1 · min?1 · year?1 in women. We conclude that age, fat mass, and lean mass are independent determinants of maximal oxygen uptake in Chinese adults.  相似文献   

6.
Despite the ongoing globalization of football culture and societies at large, there remain important cross-national and cross-local variations in the level and forms of football hooliganism. These dissimilarities thwart efforts to conceptualize and explain football hooliganism as a homogeneous phenomenon and, more specifically, seriously limit the applicability of dominant sociological theories on the subject. The author illustrates his argument with an examination of international research literature and empirical data on the social composition of one Spanish and one Dutch hooligan group. He argues that comparative research into football hooliganism should move beyond general explanations in terms of societal fault lines and towards a more detailed analysis of hooligans' subcultural identities and social interactions.  相似文献   

7.
Critical discourse analysis was used to explore and discuss data on young people’s knowledge and understanding of health, fitness and physical activity, selected from a wider study which focused on the role of secondary schools in effectively promoting physical activity. A mixed methods approach was utilised, involving an online survey to teachers in all state secondary schools in the UK (n?=?603 responding schools) and case studies centred on eight randomly selected state secondary schools from nine Government regions across England. Within each case study school, teacher interviews and pupil focus groups were conducted involving 17 teachers and 132 children aged 12–15 years, respectively. The healthism discourse was evident in the way young people talked about health, fitness and physical activity and two key themes emerged, these being: (i) issues with young people’s knowledge and understanding of health, fitness and physical activity in the form of reductive, limited and limiting conceptions; conceptual confusion; a preoccupation with appearance, weight, fat, shape and size; limited progression in learning; and complexities in understandings; and (ii) divides between young people’s health knowledge and health behaviour, and dilemmas underpinning these divides. Improved understanding of issues with young people’s knowledge and understanding of health, fitness and physical activity and of divides and dilemmas regarding associated behaviours should assist in developing critical pedagogies which challenge the dominance and stability of the healthism discourse and more effectively promote healthy, active lifestyles amongst young people.  相似文献   

8.
The purpose of this study was to compare home advantage at the top two levels of the domestic leagues of a wide selection of countries worldwide. Limited previous work has been inconclusive with home advantage at level 2 appearing at least as high as at level 1. Home advantage was quantified for the most recent seven seasons of the top two levels for 47 countries worldwide and included 168,341 matches. A paired t?test was used to assess the difference between levels for each country. Home advantage was significantly more likely to be higher at level 2 than at level 1. The difference was especially apparent in Bosnia–Herzegovina, Serbia and Iran (all p?<?0.001). Kazakhstan was the only country with a significantly higher advantage at level 1. Possible factors that might be contributing to this finding include players and referees at level 1 being better trained to avoid being influenced by crowd support. Level 2 players may be more intimidated by performing away from home, less well equipped to cope with unfamiliar surroundings and routines, and will also have travelled in less comfort.  相似文献   

9.
The relationship between health (H) and physical education (PE) has long been the subject of debate. Recently, however, the obesity crisis has raised this relationship to a new level of attention. At the risk of simplifying things, there are two ‘positions’ that seem to characterize the discourse regarding this new relationship. One position considers that the main mission of PE should now be the ‘war on obesity’. Advocates for this instrumental position tend to do research, using interventionist strategies focusing on (H)PE as a site for the promotion of physical activity. The other position argues strongly for the foregrounding of educational purposes for (H)PE and tends to pursue research by means of sociocultural research paradigms such as phenomenology, poststructuralism or critical theory. Importantly, these ‘positions’ draw on different literatures and discourses. Seldom do the advocates of these two positions speak to each other and, if and when they do, they seem to speak different languages. In this paper, I discuss the notion of academic discourse and explore, with some examples from conferences, how the conventions of academic discourse are (mis)understood and accordingly confound the development of more considered responses to the relationship between health and PE.  相似文献   

10.
《Sport Management Review》2015,18(2):207-217
In order to inform strategies to increase levels of physical activity (PA) for a healthier society, it is important to understand participation trends in leisure-time physical activity (LTPA). Little is known about the context of LTPA participation, particularly from the perspective of “sport and recreation” (S&R) categories such as organised and club-based activities. The primary aim of this study is to contribute to the sport management literature by specifically examining PA participation levels and trends in Australia over a decade, for those aged 15 years and older, through the lens of S&R. This paper also discusses the potential synergy between the public health and sport management domains with regard to LTPA/S&R. The Australian Sports Commission provided data from the Exercise, Recreation and Sport Survey (ERASS), a population survey conducted quarterly from 2001 to 2010 by computer-assisted telephone interview. Participation in LTPA was analysed by year, gender and age, in three hierarchically related categories: (1) any LTPA participation, (2) participation in an organised context, and (3) organised participation in a club. Participation rates in any LTPA increased significantly over the decade. However, this was not matched by increases in organised and/or club participation, which largely remained steady over the 10-year period. Much of the organised participation was within a club setting, and participation in this context is more likely among males than females. There is some evidence that the overall level of LTPA is increasing, which is positive for health, but there was generally no increase in club-based participation, resulting in sport contributing relatively less to overall population LTPA. However, the depth of information available from population surveys regarding club-based LTPA is insufficient to draw definitive conclusions, or make important strategic decisions about sport and health policy. There is a critical need for more comprehensive sport participation data to provide the evidence for improved programme and policy development. An avenue for this to occur may be through the integration of participation data from peak sport organisations.  相似文献   

11.
Abstract

This paper examines the effect of participating in a web-based health programme that promotes personal tracking of high school students’ own measurements of a number of health-related parameters. Danish cross-sectional survey data were used to examine the effects of the health programme on various health measures. Both quantile regression models and standard ordinary least squares (OLS) models were used to explore the correlations between the students’ participation in the health programme and their body mass index (BMI), body fat percentage, aerobic fitness, and well-being. Participation in the health programme increased BMI and aerobic fitness among students with a BMI or an aerobic fitness value ranging from the 25th percentile to the 75th percentile and reduced body fat percentage among students with the highest percentages of body fat. In addition, the health programme led to an increased feeling of wellbeing among students, especially those with high BMI levels and poor aerobic fitness. As the schools participated in the health programme on voluntary basis and at a financial cost to themselves, the positive effects of participation found can only be stated to be valid among students from committed schools.  相似文献   

12.
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13.
The aim of this study was to investigate the reliability and validity of a soccer short passing test using the Footbonaut training system. Forty-eight young skilled soccer players and 31 lesser-skilled soccer players completed a test and a retest, each involving four sessions a day of a Footbonaut short passing test (FSPT). We found significant differences in mean execution times for skilled (mean [M]?=?2487, standard deviation [SD] ?=?155) and lesser-skilled players (M?=?2682, SD?=?176) but no significant difference in accuracy (M?=?74.13, SD?=?7.65; M?=?72.19, SD?=?8.13) between groups. The results from linear mixed-effects models show that there were no significant effects of repeated measurements on execution time. In contrast, we found an estimated increase of 0.86% in accuracy per session for both groups. In conclusion, the FSPT offers a reliable and valid method to differentiate young soccer players at different competitive levels, using execution time.  相似文献   

14.
Abstract

Individuals have to reweight the respective contribution of the different sources of sensorial information for regulating posture and balance, especially during fine task execution. Given the evidences indicating strategy during swing performance as associated with prioritization of task-relevant visuospatial information for skill execution, the aim of the present work is to assess differences in visual dependency (VD) and postural control in a population of expert (EXP) and non-expert (NEXP) golfers when compared with healthy subjects (HC) and to discover possible relationships between these outcomes and swing performance. Thus, 15 golfers (EXP?=?7; NEXP?=?8) and 32 matched HC underwent otoneurological testing including video Head Impulse Test, posturography and Rod and Disk Test (RDT). Golf players also underwent a swing session procedure, which performance was measured by means of the Flightscope X2 Doppler-radar launch monitor system. EXP subjects demonstrated significant (p?<?0.05) lower values in i) counter-clockwise (CCW) and clockwise (CW) dynamic conditions when compared with both NEXP and HC subjects RDT outcome measures and ii) surface and length posturography values as compared with HC subjects. When treating golf players outcomes as ‘a continuum’, CCW and CW scores were found to positively correlate with both lateral distance and horizontal launch angle and to negatively correlate with spin rpm. In conclusion, the present study suggests that the high-level of visual-independency demonstrated by EXP subjects may be functionally related in expert golfers to an effective motor strategy preferentially not referring to an inappropriate reliance on visual input.  相似文献   

15.
This paper explores how a cohort of pre-service Health and Physical Education (HPE) teachers from an Australian university describe and construct their understandings of health and the body. Given that the courses that these undergraduates take in their degree programme present different perspectives on health and the body, a relevant question is to what extent these perspectives adequately equip these future HPE teachers to successfully teach the recently released Australian HPE curriculum. The participants in this study were 14 pre-service teachers, 11 females and 3 males, aged between 18 and 26 at the time of the first interview. The data used for this paper were taken from a larger study and were generated through interviews, the analysis of two undergraduate course profiles and an analysis of the new National HPE curriculum. Results reveal that there are some dominant discourses in health-related courses that may have a significant impact on these students. The purpose of HPE, the role of the HPE teacher and the idea of the HPE teacher as role model are also discussed. The results suggest that pre-service teachers face several challenges and dissonances between what they learn during their undergraduate programme and what the Australian HPE curriculum expects them to teach. How pre-service HPE teachers think about and relate to health and the body is important in terms of how they think about their professional practice and the influence they may have on their future pupils.  相似文献   

16.
This paper compares French- and English-language Canadian television coverage of Australian Aboriginal athlete Cathy Freeman during the 2000 Olympics using a narrative framework. The specific focus of the analysis is the representation of Freeman's political identity as an agent and symbol of Aboriginal reconciliation – the struggle for apology, reparatio, and social justice in the light of the history and legacy of colonial oppression and exclusion. Freeman has used her sporting success to signify visibly and with some controversy her identification with political Aboriginality and reconciliation, and she went into the 2000 games bearing an unusual weight of expectation, intensified by being chosen to light the Olympic cauldron, that a victory in the 400 metres would mark symbolically reconciliation between Aboriginal and non-Aboriginal Australians. The analysis generally conforms the hypothesis that the normative dimension of these expectations would be accentuated more in the French- than English-language coverage, and this resulted in a more consistently affirmative portrayal of Freeman and her performance. The English-language coverage emphasized the ambivalent nature of her role. The corollary of this was that the English-language coverage paid greater attention to the substance of Aboriginal grievances and struggle. Nonetheless, neither network saw Freeman's identity in openly critical terms: in Freeman's Olympic narrative sport and politics were allowed to mix in a relatively unproblematic way.  相似文献   

17.
The aim of this study was to analyse the important kinematic variables in elite men's and women's 20 km race walking. Thirty men and 30 women were analysed from video data recorded during the World Race Walking Cup. Video data were also recorded at four points during the European Cup Race Walking and 12 men and 12 women analysed from these data. Two camcorders operating at 50 Hz recorded at each race for 3D analysis. The two main performance determinants of speed were step length and cadence. Men were faster than women because of their greater step lengths but there was no difference in cadence. A reduction in step length was the initial cause of slowing down with later decreases in speed caused by reductions in cadence. Shorter contact times were important in optimising both step length and cadence, and faster athletes tended to have longer flight times than slower athletes. It was less clear which other kinematic variables were critical for successful walking, particularly with regard to joint angles. Different associations were found for some key variables in men and women, suggesting that their techniques may differ due to differences in height and mass.  相似文献   

18.
This article examines theories and practices of moral and physical education among the Scottish missionaries in the Malawi region of south-central Africa during late nineteenth and early twentieth centuries. Within the wider history of British imperial education and the English public school games ethic, the Scottish missionaries of the Livingstonia and Blantyre missions offer an interesting and important counterpoint to their middle-class English counterparts. Although the Scots had their own distinct educational traditions which shaped their pedagogical programmes in Africa, they were not unaffected by the games ethic. Drill and team games gradually became an important part of missionary education in Blantyre and Livingstonia, with the holistic aim of developing the body, mind and moral character of the mission pupils. In Malawi, the games ethic, first introduced by middle-class Edinburgh missionaries, developed alongside an ‘industrial ethic’, and a distinctly ‘Scottish blend’ of missionary education that combined Scottish industrial and English non-industrial traditions emerged.  相似文献   

19.
Abstract

The aims of this study were to examine the acute effects of static stretching on peak torque, work, the joint angle at peak torque, acceleration time, isokinetic range of motion, mechanomyographic amplitude, and electromyographic amplitude of the rectus femoris during maximal concentric isokinetic leg extensions at 1.04 and 5.23 rad · s?1 in men and women. Ten women (mean ± s: age 23.0 ± 2.9 years, stature 1.61 ± 0.12 m, mass 63.3 ± 9.9 kg) and eight men (age 21.4 ± 3.0 years, stature 1.83 ± 0.11 m, mass 83.1 ± 15.2 kg) performed maximal voluntary concentric isokinetic leg extensions at 1.04 and 5.23 rad · s?1. Following the initial isokinetic tests, the dominant leg extensors were stretched using four static stretching exercises. After the stretching, the isokinetic tests were repeated. Peak torque, acceleration time, and electromyographic amplitude decreased (P≤ 0.05) from pre- to post-stretching at 1.04 and 5.23 rad · s?1; there were no changes (P > 0.05) in work, joint angle at peak torque, isokinetic range of motion, or mechanomyographic amplitude. These findings indicate no stretching-related changes in the area under the angle – torque curve (work), but a significant decrease in peak torque, which suggests that static stretching may cause a “flattening” of the angle – torque curve that reduces peak strength but allows for greater force production at other joint angles. These findings, in conjunction with the increased limb acceleration rates (decreased acceleration time) observed in the present study, provide tentative support for the hypothesis that static stretching alters the angle – torque relationship and/or sarcomere shortening velocity.  相似文献   

20.
This article takes a point of departure in the debate whether physical education should consider a limited or an increased commitment towards public health goals and a public health agenda. The article further discusses the relationship between physical activity and health, and the perspective of health in physical education. This is done through a critique of the dominance of a pathogenic perspective of health, as well as through a salutogenic approach regarding health as a process. A salutogenic approach makes, as suggested in the article, other questions—salutogenic questions—possible. In this sense, physical activity and movement can be regarded as something more than mere protection against disease or overweight, and by posing salutogenic questions we can enrich our understanding of the relation between physical activity and health, and in consequence richness to the perspective of health in physical education. With a salutogenic approach, the pupils’ unique and common experiences of health, movement, body ideals or outdoor-life can meet a wider perspective of health. This would facilitate a health perspective in physical education that draws attention to the qualities, abilities and knowledge that pupils can develop, and, in the name of learning health, point the way to the possible contribution of physical education in pupils’ health development in terms of how physical education can enrich their lives, strengthen them as healthy citizens and contribute to a sustainable (health) development.  相似文献   

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