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This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Determining the Value of Cultural Goods: How Much (or How Little) Does Contingent Valuation Tell Us? 总被引:1,自引:0,他引:1
David Throsby 《Journal of Cultural Economics》2003,27(3-4):275-285
Contingent valuation methods (CVM) are now well established as a means of measuring the nonmarket demand for cultural goods and services. When combined with valuations provided through market processes (where relevant), an overall assessment of the economic value of cultural commodities can be obtained. Within a neoclassical framework, such assessments are thought to provide a complete picture of the value of cultural goods. But are there aspects of the value of cultural goods which are not fully captured, or not captured at all, within such a model? This paper argues that CVM provides an incomplete view of the nonmarket value of cultural goods, and that alternative measures need to be developed to provide a fuller account. 相似文献
46.
Cerebral activity, as reflected by power in the alpha waveband (8-13 Hz), was examined prior to the performance of three tasks with different effort and accuracy requirements. The study aimed to further investigate changes in activity observed in an earlier study in which expert karate performers exhibited significant increases in alpha band power during preparation for a training task. In contrast to the earlier research, the high effort task produced a significant decrease in 'alpha' power prior to performance. 'Alpha' power prior to the high accuracy task showed significant differences mediated by the outcome. Successful performance was preceded by higher levels of 'alpha' power than unsuccessful attempts. The reported use of a cognitive strategy on the first task produced a significant difference in activity, lower alpha power being associated with the use of such a technique. 相似文献
47.
D A Sedlock 《Research quarterly for exercise and sport》1991,62(2):213-216
This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO2) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO2 and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO2 and HR were measured continuously during the postexercise period until baseline VO2 was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p greater than .05). Mean (+/- SD) values were 9.2 +/- 3.3 and 10.4 +/- 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p greater than .05) between the upper body (22.9 +/- 13.7 min) and lower body (24.2 +/- 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO2 or quantity of active muscle mass associated with these two types of exercise. 相似文献
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Data from the International Social Survey Program indicate considerablevariation in the desire of respondents for increased spendingon the environment in Australia, Austria, Great Britain, theUnited States, and West Germany. This paper explores this variationwith the following objectives: (1) to determine the extent towhich the social bases of environmental concern are consistentacross nations; (2) to determine how the issue of the environmenthas been politicized in the five industrialized nations, focusingon the association of Old Leftist concerns and environmentalconcern; and (3) to determine the extent to which the socialbases of environmental concern can explain the cross-nationalvariation. The study usesa regression analysis, testing variablesrepresenting the social bases of environmental concern frompast research in the United States, a scale representing commitmentto the platform of the Old Left, and dummy variables for eachcountry. The results show that the social bases of environmentalconcern are the same in the five countries studied, includinga consistent positive association of Old Leftism with environmentalconcern. However, substantial variation between countries inthe overall level of concern remains. Potential sources of theremaining variation are examined. 相似文献
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This study investigates professional autonomy as experienced by psychotherapists in Korea and in the United States using data collected as part of a collaborative international study of the development of psychotherapists (Orlinsky et al. (1999). Psychotherapy Research, 9(2), 127–153; Orlinsky & Rønnestad, (2005). How psychotherapists develop: A study of therapeutic work and professional growth. Washington, DC: American Psychological Association). The major aims are: to compare the extent of professional autonomy experienced by psychotherapists in Korea and by their counterparts in the USA; and to explore the professional and social correlates of the professional autonomy experienced by Korean therapists and compare these with the correlates of autonomy experienced by American therapists. These aims are pursued through analyses of a database of questionnaire responses. Results indicate that Korean therapists, compared to American therapists in our sample experience significantly lower levels of professional autonomy. For Korean therapists, whether they have a salient theoretical orientation in their practice is the single most important influence in their experience of work autonomy. Seniority and work setting are also significant correlates of autonomy for the Korean therapists. Similar to Korean therapists, seniority and having a salient orientation are also important influences on the way American therapists experience professional autonomy. American therapists, who work in independent practice experience higher work autonomy, whereas American social workers tend to experience lower professional autonomy. 相似文献