The physical demands of elite English rugby union   总被引：1，自引：1，他引：0  

Roberts SP  Trewartha G  Higgitt RJ  El-Abd J  Stokes KA 《Journal of sports sciences》2008,26(8):825-833

The aim of this study was to assess the physical demands of elite English rugby union match-play. Player movements were captured by five distributed video cameras and then reconstructed on a two-dimensional plane representing the pitch. Movements based on speeds were categorized as standing, walking, jogging, and medium-intensity running (low-intensity activity), and high-intensity running, sprinting, and static exertion (scrummaging, rucking, mauling, and tackling) (high-intensity activity). Position groups were defined as forwards (tight and loose) and backs (inside and outside). Backs travelled more total distance than forwards (6127 m, s=724 vs. 5581 m, s=692; P<0.05) and greater distances in walking (2351 m, s=287 vs. 1928 m, s=2342; P<0.001) and high-intensity running (448 m, s=149 vs. 298 m, s=107; P<0.05). Forwards performed more high-intensity activity than backs (9:09 min:s, s=1:39 vs. 3:04 min:s, s=1:01; P<0.001), which was attributable to more time spent in static exertion (7:56 min:s, s=1:56 vs. 1:18 min:s, s=0:30; P<0.001), although backs spent more time in high-intensity running (0:52 min:s, s=0:19 vs. 1:19 min:s, s=0:26; P=0.004). Players travelled a greater distance in the first 10 min compared with 50-60 and 70-80 min, but there was no difference in the amount of high-intensity activity performed during consecutive 10-min periods during match-play. These results show the differing physical demands between forwards and backs with no evident deterioration in high-intensity activity performed during match-play.  相似文献   

Physiological determinants of climbing-specific finger endurance and sport rock climbing performance   总被引：1，自引：1，他引：0  

MacLeod D  Sutherland DL  Buntin L  Whitaker A  Aitchison T  Watt I  Bradley J  Grant S 《Journal of sports sciences》2007,25(12):1433-1443

The aim of the study was to examine several physiological responses to a climbing-specific task to identify determinants of endurance in sport rock climbing. Finger strength and endurance of intermediate rock climbers (n = 11) and non-climbers (n = 9) were compared using climbing-specific apparatus. After maximum voluntary contraction (MVC) trials, two isometric endurance tests were performed at 40% (s = 2.5%) MVC until volitional exhaustion (continuous contractions and intermittent contractions of 10 s, with 3 s rest between contractions). Changes in muscle blood oxygenation and muscle blood volume were recorded in the flexor digitorum superficialis using near infra-red spectroscopy. Statistical significance was set at P < 0.05. Climbers had a higher mean MVC (climbers: 485 N, s = 65; non-climbers 375 N, s = 91) (P = 0.009). The group mean endurance test times were similar. The force-time integral, used as a measure of climbing-specific endurance, was greater for climbers in the intermittent test (climbers: 51,769 N x s, s = 12,229; non-climbers: 35,325 N x s, s = 9724) but not in the continuous test (climbers: 21,043 N x s, s = 4474; non-climbers: 15,816 N x s, s = 6263). Recovery of forearm oxygenation during rest phases (intermittent test) explained 41.1% of the variability in the force-time integral. Change in total haemoglobin was significantly greater in non-climbers (continuous test) than climbers (P = 0.023--40% test timepoint, P = 0.014--60% test timepoint). Pressor responses were similar between groups and not related to the force-time integral for either test. We conclude that muscle re-oxygenation during rest phases is a predictor of endurance performance.  相似文献   

Choice of sprint start performance measure affects the performance-based ranking within a group of sprinters: which is the most appropriate measure?     

Bezodis NE  Salo AI  Trewartha G 《Sports biomechanics / International Society of Biomechanics in Sports》2010,9(4):258-269

Sprint start performance has previously been quantified using several different measures. This study aimed to identify whether different measures could influence the performance-based ranking within a group of 12 sprinters, and if so, to identify the most appropriate measure. None of the 10 performance measures ranked all sprinters in the same order; Spearman's rho correlations between different block phase measures ranged from 0.50 to 0.94, and between block phase measures and those obtained beyond block exit from 0.66 to 0.85. Based on the consideration of what each measure quantifies, normalised average horizontal external power was identified as the most appropriate, incorporating both block velocity and the time spent producing this velocity. The accuracy with which these data could be obtained in an externally valid field setting was assessed against force platform criterion data. For an athlete producing 678 +/- 40 W of block power, a carefully set-up manual high-speed video analysis protocol produced systematic and random errors of +5 Wand +/- 24 W, respectively. Since the choice of performance measure could affect the conclusions drawn from a technique analysis, for example the success of an intervention, it is proposed that external power is used to quantify start performance.  相似文献   

The Personality Characteristics of Acceptors and Rejectors of the Newer Educational Media among Secondary Teachers of Wisconsin     

Alfred D. Grant 《British journal of educational technology : journal of the Council for Educational Technology》1972,3(2):129-136

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Letter from Detroit: The courts and the schools     

William R. Grant 《The Urban Review》1975,8(2):145-152

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Letter to the Editors     

Ron Grant 《Literacy》1980,14(1):41-42

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ISTANBUL UNIVERSITY     

Michael Grant 《Higher Education Quarterly》1954,8(4):348-351

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Pursuing Internationalization as a Means to Advance the Academic Mission of the University: An Australian Case Study     

Grant McBurnie 《Higher Education in Europe》2000,25(1):63-73

Strategies for internationalization are central to the shape Monash University has taken and the goals it has set for its future. Using Monash as a case study, this article examines issues involved in the pursuit of internationalization through the internationalization of the composition of the student body, the establishment and enhancement of a presence overseas, and the internationalization of the educational experience. The guiding principle stressed throughout is that, in order to remain central rather than marginal, international activities must significantly advance the core academic functions of the university.  相似文献   

Posthumanism and educational research     

Barbara M. Grant 《高等教育研究与发展》2016,35(3):638-640

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The Knowledge We Have Lost in Information: The History of Information in Modern Economics,by Philip Mirowski and Edward Nik-Khah     

Grant Bollmer 《Journal of Cultural Economy》2018,11(2):169-172

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