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991.
Zero-sum aspects of sport have generated a number of ethical concerns and a similar number of defenses or apologetics. The trick has been to find a middle position that neither overly gentrifies sport nor inappropriately emphasizes the significance of winning and losing. One such position would have us focus on the process of trying to win over the fact of having one. It would also ameliorate any harms associated with defeat by pointing out that benefits like achievement, excellence, and moral development are available to winner and loser alike. Relying on the notion of ‘frame’ introduced by Polanyi, I argue that this approach underplays the poignant drama of sport (including the sting of defeat) and thus, seeks redemption at too high a cost. I argue for a version of red-blooded competition that is justified more by transcendence than mitigation, more by a willingness to play again tomorrow than civility during any single contest. I analyze sport in terms of its receptivity to such repetition and find that epistemological uncertainty, enhanced by the presence of chance in sport, renders repeat engagements both sensible and attractive. I conclude that sport verdicts, unlike outcomes in war, business, and love, do not settle things. Rather they invite both winner and loser alike to ‘play again tomorrow’.  相似文献   
992.
For the last 15 years a statistical analysis of distances skied and of alpine skiing accidents has been performed in the Davos‐Klosters skiing area, a ‘closed’ skiing area, where every skier has to return from the top to the bottom station. Distance skied is measured by vertical drop in 106 km determined by calculations from frequency surveys by lift‐operators. About 2.5 million km per season have been skied during the past years, a number remaining constant for the last 15 years. In the same time the requirement for rescue‐transports in this area has shown a decline of 46% to 288 transports per season due to a decrease of the number of injuries with initial immobilization. Therefore the so‐called transport‐quotient (one rescue‐transport per 104 km of vertical drop skied) has decreased from its initial value of 4 to 1 per 104 km. During the same time all winter sport injuries were analysed at the hospital of Davos. About 90% are injuries caused by alpine skiing resulting in a total of 17 246 alpine skiing injuries for the last 15 years. There is a great decline in the incidence of lower leg fractures with a contrary development of knee injuries. Today half of the lower leg injuries are knee injuries (280 knee injuries out of a total of 1250 alpine skiing accidents per season). There is a gradual increase of upper extremity injuries from 17% of all skiing injuries in 1972 to 35% in 1976. A Swiss multicentre study on skiing safety shows comparable injury patterns in other skiing areas. The average injury‐severity measured by several parameters is declining.

In a technical investigation of skiing equipment of 1072 persons who sustained an accident, only 32% had ski bindings with tolerable frontal release and 17% with tolerable torsional release. Parallel measurements of bindings of 600 non‐injured skiers gave the same alarming results. More research on the correlation between binding adjustment and knee injuries is needed.  相似文献   
993.
One-dimensional models of a golf ball are useful in modelling near-normal (90°) impact. The model described here has two masses connected by a non-linear spring in parallel with a non-linear damper. The behaviour of this system in collision with an infinite rigid mass is compared with the results of tests involving real golf balls. Values of the four unknown constants are found by fitting the model results, over a range of impact speeds from zero to 50 m· s -1 , to the coefficient of restitution and duration of contact found in the tests. The simplest model (Model 1) was a good fit for duration of contact over the whole range of impact speeds, but for the coefficient of restitution only at high speed (above 20 m· s -1 ). However, when used with a similar model of a flexible faced club, the simple model predicted the coefficient of restitution of the club-ball combination, determined by direct testing, quite well and as such is a useful screening tool. More complicated Models 2 and 3 fitted the rigid target coefficients of restitution better at low speed than Model 1. However, Models 2 and 3 have other disadvantages and are no better than Model 1 for high-speed impact with flexible faced clubs.  相似文献   
994.
Abstract

Research into the science and medicine underlying cricket performance and injury has progressed since the First World Congress of Science and Medicine in Cricket in 1999. This review covers material on the physiological and psychological demands of the game and preparation for it, the biomechanics and motor control of cricket skills, the psychology of team dynamics, performance analysis and cricket injuries. Technological aspects of cricket equipment are also covered, where such research could influence injury risk or player performance. Fielding remains the least studied of the skills. Much more research needs to be done before we can gain a full understanding of the scientific aspects of the game. There is a need to address common definitions of injury, along with more research into injury mechanisms. Research on batting needs to bring together motor control and biomechanics more fully. The fitness demands of the game are still poorly understood, along with the mechanisms causing fatigue. Evaluation of the efficacy of intervention strategies needs to continue and to develop. The applications of research need to be communicated more to coaches and players — for example, in team dynamics — so that they can be applied, and tested further, in international matches.  相似文献   
995.
This paper had three aims. The first was to review research carried out on the home advantage from 1992 to the present. The second was to examine the extent to which a conceptual framework proposed by Courneya and Carron () was/is viable as a tool to highlight and organize an understanding of the home advantage. The final aim was to provide suggestions for future research.  相似文献   
996.
Abstract

The aim of this study was to compare optimization and correction procedures for the determination of peak power output during friction-loaded cycle ergometry. Ten male and 10 female sports students each performed five 10-s sprints from a stationary start on a Monark 864 basket-loaded ergometer. Resistive loads of 5.0, 6.5, 8.0, 9.5, and 11.0% body weight were administered in a counterbalanced order, with a recovery period of 10 min between sprints. Peak power was greater and occurred earlier, with less work having been done before the attainment of peak power, when the data were corrected to account for the inertial and frictional characteristics of the ergometer. Corrected peak power was independent of resistive load (P > 0.05), whereas uncorrected peak power varied as a quadratic function of load (P < 0.001). For males and females, optimized peak power (971 ± 122 and 668 ± 37 W) was lower (P < 0.01) than either the highest (1074 ± 111 and 754 ± 56 W respectively) or the mean (1007 ± 125 and 701 ± 45 W respectively) of the five values for corrected peak power. Optimized and mean corrected peak power were highly correlated both in males (r = 0.97, P < 0.001) and females (r = 0.96, P < 0.001). The difference between optimized and mean corrected peak power was 37 ± 30 W in males and 33 ± 14 W in females, of which approximately 15 W was due to the correction for frictional losses. We conclude that corrected peak power is independent of resistive load in males and females.  相似文献   
997.
Abstract

Rowers sit on a seat that slides relative to the boat/ergometer. If a rower lifts him or herself from this sliding seat at any time, the seat will move away from under them and the rowing action is disrupted. From a mechanical perspective, it is clear that the need for the rower to remain in contact with the sliding seat at all times imposes position-dependent constraints on the forces exerted at the oar handle and the footstretcher. Here we investigate if the mechanical power output during rowing, which is strongly related to these forces, might be improved if the contact with the sliding seat was of no concern to the rower. In particular, we examine if elimination of these constraints by strapping the rower to the sliding seat leads to an increase in performance during the start on a standard rowing ergometer. Eleven well-trained female rowers performed 5-stroke starts in normal and strapped conditions. Handle force, vertical seat force, footstretcher force, and handle kinematics were recorded, from which mechanical power and work output were calculated. Most of the relevant mechanical variables differed significantly between the normal and strapped conditions. Most importantly, mechanical power output (averaged over the 5-stroke start) in the strapped condition was 12% higher than in the normal condition. We conclude that strapping a rower's pelvis to the sliding seat allows more vigorous execution of the stroke phases, resulting in a substantial improvement in performance during the start of ergometer rowing.  相似文献   
998.
Abstract

In this study, we examined the effects of a supervised, heart rate intensity prescribed walking training programme on cardiorespiratory fitness and glycaemic control in people with type 2 diabetes mellitus. After receiving local ethics approval, 27 individuals (21 males, 6 females) with type 2 diabetes were randomly assigned to an experimental (“walking”) or control group. Participants completed a Balke-Ware test to determine peak heart rate, peak oxygen consumption ([Vdot]O2peak), and peak gradient. The walking group then completed a 7-week (four sessions a week) supervised, heart rate prescribed walking training programme, whereas the control group continued daily life. After training, participants completed another Balke-Ware test. Fasting blood glucose and glycosylated haemoglobin were measured at rest. The results showed that walking training elicited 80% (s = 2) of peak heart rate and a rating of perceived exertion of 11 (s = 1). Peak heart rate and [Vdot]O2peak were higher in the walking than in the control group after training (P < 0.05). Based on the peak gradient before training, the respiratory exchange ratio was significantly lower (P < 0.05) and there was a strong trend for [Vdot]O2 (P = 0.09) and heart rate (P = 0.09) to be lower after training at the same gradient in the walking compared with the control group. These improvements increased walking peak gradient by 5 min (s = 4 min) compared with the control (P < 0.05). There was no change in fasting blood glucose or glycosylated haemoglobin after training. Despite no change in glycaemic control, heart rate prescribed walking improved peak and sub-maximal cardiorespiratory responses. The beneficial adaptations support the use of heart rate monitoring during walking in people with type 2 diabetes mellitus.  相似文献   
999.
Abstract

To better understand the contextual interference effect, in two experiments we investigated a form of practice schedule that provided novices with systematic increases in contextual interference. This new type of practice schedule was compared with traditional blocked and random scheduling for two types of sports skills. In Experiment 1, we tested the hypothesis that practising variations of the same task with systematic increases in contextual interference would lead to superior performance compared with blocked or random scheduling. Participants practised golf putting tasks following a blocked, random or increasing schedule, which involved initial blocked trials, followed by serial practice trials, and ended with random scheduling. Participants who followed the increasing schedule had superior retention test performance. In Experiment 2, we tested if these learning benefits were observed when learning tasks controlled by different generalized motor programs. Participants practised three different basketball passes (chest, overhead, single arm) in a blocked, random or increasing schedule. Participants practising with gradual increases in contextual interference performed better on retention and transfer tests than participants practising with blocked or random scheduling. The results of these two experiments indicate that a practice schedule offering systematic increases in contextual interference facilitates skill learning.  相似文献   
1000.
Abstract

The relative length of the second and fourth digits (2D:4D) is a putative marker for prenatal testosterone. Low 2D:4D has been reported to correlate with high performance in sport in general. Here, for the first time, we examine the relationship between 2D:4D and performance in elite rugby players. The 44 players (28 forwards, 16 backs) were drawn from the Ospreys Rugby Union Club and 44 age-matched controls. The measures of performance comprised age-adjusted number of international performances (caps) for Wales, a comparison of coaches' first-choice League team with others, and the number of tries scored by backs in club matches. Compared with controls, players were larger and had lower 2D:4D for the right and left hand. With regard to number of caps, players with low 2D:4D in their right hand and low right 2D:4D compared with their left (right ? left 2D:4D difference) had high numbers of caps. First-choice players did not differ significantly from second-choice players in their 2D:4D but they did have a lower right ? left 2D:4D difference than second-choice players. Low right 2D:4D and low right ? left 2D:4D difference were significantly linked with large numbers of tries. We conclude that low right 2D:4D and low right ? left 2D:4D difference are predictors of high rugby performance.  相似文献   
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