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11.
The aim of this study was to examine acute physiological responses and time-motion characteristics associated with three different small-sided soccer game formats in youth players. Sixteen male soccer players aged 16.3+/-0.6 years (mean+/-s) completed three variations of a small-sided game (i.e. 2 vs. 2, 4 vs. 4, and 6 vs. 6 players) in which heart rate, rating of perceived exertion (RPE), blood lactate concentration, and time-motion characteristics were recorded. The pitch size was altered to keep the relative pitch area per player consistent for each game format. The 2 vs. 2 games exhibited greater blood lactate, heart rate, and RPE responses compared with 4 vs. 4 and 6 vs. 6 games (P<0.05). The players travelled less (P<0.05) distance at speeds of 0-7 km.h(-1) in the 4 vs. 4 compared with the 2 vs. 2 games (1128+/-10 m and 1176+/-8 m, respectively). Average maximal sprint distances above 18 km.h(-1) were lower (P<0.05) in 2 vs. 2 than in 4 vs. 4 and 6 vs. 6 games (11.5+/-3.9 m, 15.3+/-5.5 m, and 19.4+/-5.9 m, respectively), and in 4 vs. 4 compared with 6 vs. 6 games. The results show that as small-sided game formats decrease in size and relative pitch area remains constant, overall physiological and perceptual workload increases. 相似文献
12.
Maximal work production following two levels of artificially induced metabolic alkalosis 总被引：2，自引：1，他引：1
D C McKenzie K D Coutts D R Stirling H H Hoeben G Kuzara 《Journal of sports sciences》1986,4(1):35-38
In order to determine the influence of two artificially induced alkalotic states on the ability to perform maximal exercise, six male subjects (mean age, 22.0 years; mean height, 176.8 cm; mean weight, 69.1 kg; mean VO2 max, 3.83 l min-1) were studied during three experimental trials. The subjects performed six 60-s cycling bouts, at a work rate corresponding to 125% VO2 max, with 60 s recovery between work bouts; these regimens were performed 1 h after the ingestion of a solution containing either; I, placebo; II, NaHCO3 in a dosage of 0.15 g per kg body weight; or III, NaHCO3 0.30 g per kg body weight. The sixth work bout was continued until the pedal velocity dropped below 50 rev min-1. Total work done for the entire work period was calculated. Blood samples were taken from a forearm vein prior to the exercise bouts for analysis of pH and HCO3. The results showed a significant pre-exercise difference in pH and HCO3 for all conditions (P less than 0.01). In conditions where artificial alkalosis had been achieved prior to exercise there was significant increase in the work produced: I, 121.6 kJ; II, 133.1 kJ; III, 133.5 kJ (P less than 0.05). The time to fatigue in the six bout was also significantly increased; I, 74.7 s; II, 111.0 s; III, 106.0 p (P less than 0.05). There were no significant differences between conditions II and III. Thus augmentation of the bicarbonate reserves has a significant positive effect on the energy metabolism in interval-type exercise, leading to an increase in the work done and in the time to fatigue.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
13.
Young adult soccer players often encounter difficulty progressing from youth competition to being regularly selected for high-level, open-age competition. In an attempt to increase the playing opportunities of semi-professional and amateur under-21 players in first teams, the Royal Belgian Football Association required national division teams to include at least two players younger than 21 in their match selection (under-21 rule). Over four seasons, the following variables were analysed across 2138 semi-professional and amateur soccer players aged 16-39 years: (1) the number of times a player was selected to be in the first team squad; (2) the number of times a player was selected to play in the starting line-up; and (3) the number of minutes played. Chi-square analysis demonstrated that second and third division teams had complied with the new selection regulations. However, two-way analysis of variance of individual player data revealed no increase in the number of playing minutes in the under-21 group. It would appear that many teams had complied with the new regulations by selecting young players as substitutes. The results highlight the difficulties that talented young soccer players experience progressing from youth to senior competition. We conclude that the rule imposed by the Royal Belgian Football Association has failed to improve the playing opportunities of young adult soccer players. Alternative strategies for increasing playing opportunities for young talented players are required. 相似文献
14.
Building Better Communities for Children: Community Implementation and Evaluation of the Australian Early Development Index 总被引：1，自引：0，他引：1
Mary Sayers Melissa Coutts Sharon Goldfeld Frank Oberklaid Sally Brinkman Sven Silburn 《Early education and development》2007,18(3):519-534
Since 2004 the Australian Early Development Index (AEDI) has been completed in 54 Australian communities over seven states and territories on more than 30,000 children. A concurrent systematic evaluation of community implementation and use of the AEDI was undertaken that included both a process and impact component. The purpose of this paper is to discuss the evaluation findings between 2004 and 2006. Results have shown there are a number of barriers and facilitators for communities in implementing the AEDI, disseminating results, and planning for community actions. The evaluation findings indicate AEDI implementation helps raise awareness of the importance of early childhood development, assists communities to work more collaboratively and to strategically plan actions to work towards improving outcomes for children. 相似文献
15.
Warren Hunt Colin Birch Jeff Coutts Frank Vanclay 《The Journal of Agricultural Education and Extension》2013,19(1):9-26
Abstract Purpose: This article outlines the development of extension as a discipline in Australia, its organization, and the ideological changes that have occurred from the second half of the nineteenth century through to the present. Design/Methodology/Approach: It considers the evolution of extension across the different states of Australia from a national perspective and describes how the research development and extension (RD&E) complex has rotated through cycles of crises, highs, awakenings in thought and practice, and periods where achievements and institutions unravel. Findings: Discussed is the tension between public and private sector extension, as well as the successes and failures of various paradigms. It considers the impacts of different agricultural policy on Australian agricultural RD&E across the decades. In particular it deals with the current ‘unravelling’ of the agricultural RD&E system in Australia, and tries to anticipate future demands on agricultural extension and how these services might be delivered into the future. Practical Implications: The article challenges the reader to consider the discipline of extension as a subset of the greater society in which it exists. It provides an insight into how the agricultural research, development and extension capacity of a nation can be observed to ebb and flow over generations in accord with the rhythm of society. Originality/Value: The article presents a perspective that has not been fully captured or understood until now. 相似文献
16.
Abstract This study examined the relationship between intensity of training and changes in hydration status, core temperature, sweat rate and composition and fluid balance in professional football players training in the heat. Thirteen professional football players completed three training sessions; “higher-intensity” (140 min; HI140), “lower-intensity” (120 min; LI120) and “game-simulation” (100 min; GS100). Movement demands were measured by Global Positioning System, sweat rate and concentration were determined from dermal patches and body mass change. Despite similar environmental conditions (26.9 ± 0.1°C and 65.0 ± 7.0% relative humidity [Rh]), higher relative speeds (m · min?1) and increased perceptions of effort and thermal strain were observed in HI140 and GS100 compared with LI120 (P < 0.05). Significantly (P < 0.05) greater sweat rate (L · h?1) and electrolyte losses (g) were observed in HI140 and GS100 compared with LI120. Rate of rise in core temperature was correlated with mean speed (r = 0.85), session rating of perceived exertion (sRPE) (r = 0.61), loss of potassium (K+) (r = 0.51) sweat rate (r = 0.49), and total sweat loss (r = 0.53), with mean speed the strongest predictor. Sodium (Na+) (r = 0.39) and K+ (r = 0.50) losses were associated with total distance covered. In hot conditions, individualised rehydration practices should be adopted following football training to account for differences in sweat rate and electrolyte losses in response to intensity and overall activity within a session. 相似文献
17.
AbstractThis study examined the birth distribution for adolescent (i.e. <20 years) and mature age players (i.e. ≥20 years) selected in the Australian Football League (AFL) National Draft between 2001 and 2012. Birth-date information was accessed for all first time AFL national draftees and players were then classified as either adolescent (N = 736) or mature age (N = 70) draftees. Chi-squared analysis showed a clear bias in the birth distribution of adolescent draftees towards players born in the first part of the classification period for both quartile (P < 0.001) and half-year (P < 0.001) compared to the Australian national population. There was a reverse relative age effect (RAE) for mature age draftees, with a significant bias towards players born in the latter part of the selection period for both quartile (P = 0.047) and half-year (P = 0.028) compared to the Australian national population. The selection bias towards relatively older players in adolescent AFL draftees may be related to advanced physical and psychological maturity, and exposure to higher-level coaching compared to their younger counterparts. The reverse RAE in mature age draftees is a novel finding and supports the need for strategies to encourage continued participation pathways for talented Australian football players born later in the selection year. 相似文献
18.
Aaron J. Coutts 《Journal of sports sciences》2014,32(20):1829-1830
19.
What are the main purposes of drawing in the secondary art and design curriculum? What are Scottish art teachers' views on the role and function of drawing? How is drawing taught in Scottish schools? These three broad questions formed the basis of the research reported in this article. The small‐scale study, carried out between June 2002 and June 2004 will, the authors hope, be of interest to art educators seeking to explore the teaching of drawing as a key component of art and design education. In this article, we report on the background to the study, the place of drawing in Scottish art education, the methodology used, discuss some of the respondents' comments and conclude with some reflections and thoughts for future study. 相似文献
20.
Courtney Sullivan Thomas Kempton Patrick Ward Aaron J. Coutts 《Journal of sports sciences》2020,38(7):773-779
ABSTRACTThis study investigated the association between talent selection criteria, draft order and match performance in professional Australian Football players. Physical performance results from the Australian Football League (AFL) National Draft combine and non-performance based talent selection criteria were collated for all players drafted in the National Draft with selections 1–80 between 2003 and 2008 (n = 318). Match performance was assessed via the AFL Player Ranking metric that was provided by a commercial statistical provider (Champion Data Pty Ltd). A combination of stepwise multiple regression and linear mixed model analyses examined the influence of National Draft combine physical performance assessments and non-performance based talent selection criteria on draft order and future match performance. Earlier draft selection was associated with Under-18 all Australian team selection, height, Under-18 National Championship participation and indigenous status. The 20 m sprint and state of origin were associated with later draft selection. Under-18 all Australian team selection increased both Player Ranking/game and total Player Ranking. Under-18 all Australian team selection displays efficacy for selecting players with the potential for success. 相似文献