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91.
Abstract

In this study, we wished to investigate the factors that determine the direction of the spin axis of a pitched baseball. Nineteen male baseball pitchers were recruited to pitch fastballs. The pitching motion was recorded with a three-dimensional motion analysis system (1000 Hz), and the orientations of the hand segment in a global coordinate system were calculated using Euler rotation angles. Reflective markers were attached to the ball, and the direction of the spin axis was calculated on the basis of their positional changes. The spin axis directions were significantly correlated with the orientations of the hand just before ball release. The ball is released from the fingertip and rotates on a plane that is formed by the palm and fingers; the spin axis of the ball is parallel to this plane. The lift force of the pitched baseball is largest when the angular and translational velocity vectors are mutually perpendicular. Furthermore, to increase the lift forces for the fastballs, the palm must face home plate.  相似文献   
92.
Abstract

The frequency of one-legged stance and two-legged stance differs considerably among sports. We therefore expect the balance ability of athletes from different sports to vary. This study compared the sway characteristics during a static one-legged stance of soccer players, basketball players, swimmers, and non-athletes. The centre of pressure sway during one-legged stance of ten male participants representing each of the four groups was measured using a stabilometer. Centre of pressure sway was assessed by four sway factors: sway velocity, anterior-posterior sway, horizontal sway, and high-frequency sway. None of the four groups of participants showed significant differences in body sway between standing on the dominant leg and standing on the non-dominant leg. The soccer players had more high-frequency sway and less anterior-posterior sway and horizontal sway than the basketball players, swimmers, and non-athletes. These results suggest that soccer players have superior ability to maintain a stable one-legged stance. Further study is required to determine how much of the superior balance ability in soccer players is innate and how much is developed through training, as well as to determine the relationship between balance ability and playing performance.  相似文献   
93.
Abstract

To clarify the physical and mental fatigue caused by intense exercise and the relationship between the two types of fatigue, we examined changes in anthropometric and biochemical variables, neutrophil function, and the Profile of Mood States (POMS) questionnaire in 13 female university judoists attending a one-week training camp. Blood glucose, total cholesterol, haemoglobin, leukocyte count, IgG, and phagocytic activity all decreased after the training camp compared with baseline (P ≤ 0.046). Aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and neutrophil oxidative burst activity increased after the training camp (P ≤ 0.007). Of the POMS scores, that for Fatigue increased after the training camp (P = 0.041) and that for Vigour decreased (P = 0.042). The changes in several POMS scores correlated with the changes in blood biochemical variables. In particular, the change in Total mood disturbance was negatively associated with changes in myogenic enzymes (P ≤ 0.032). Our results suggest that intense exercise during training camps for female judoists leads to the appearance and accumulation of mental and physical fatigue, which are related to each other.  相似文献   
94.
Abstract

We examined the extent to which attributions are consistent in the days following competition and how attributions made immediately after competition may influence the temporal patterning of emotions experienced in response to competition. A sample of 60 adult female golfers completed measures of performance satisfaction, causal attribution, and emotion immediately after competition, 5 h after competition, and 2 days after competition. Repeated-measures multivariate analysis of covariance indicated that attributions did not change over this period. Emotions showed a significant decrease in intensity over the 5-h post-competition period. Regression analyses indicated that changes in anger and dejection were more likely in the case of less successful performances. For anger, attributions moderated this level of change. Golfers experienced anger for a longer period when they identified the cause of poor performance as stable rather than unstable. Thus, in the present sample although attributions did not change over 2 days, the longevity of anger depended on the attributions made immediately after competition.  相似文献   
95.
Abstract

Pedometers have been identified as a tool for health professionals to promote physical activity. This study, which aimed to evaluate the effectiveness of wearing a pedometer on general practitioners' attitudes to promoting physical activity, was a pragmatic, multi-centred, randomized controlled trial within a primary care trust in England. The participants were 102 general practitioners (GPs). Eighty-five (48 males, 37 females) of the GPs completed pre and post questionnaires, 43 of whom were in the intervention group. Statistical analysis revealed no significant changes between the control and intervention groups for attitude to engage in physical activity (t 83 = 1.13, CI ?0.362 to 0.099) or attitude to promote physical activity in their patients (t 83 = 1.7, CI ?0.593 to 0.045). A higher volume of walking was significantly correlated with a more positive attitude to engage in physical activity (r = 0.58, P < 0.01) but not with a more positive attitude to promoting physical activity. Wearing a pedometer had no significant effect on GPs' attitudes to engaging in physical activity or promoting physical activity in their patients.  相似文献   
96.
97.
Abstract

Three textiles with increasing compressive surface were compared with non-compressive conventional clothing on physiological and perceptual variables during sub-maximal and maximal running. Fifteen well-trained endurance athletes (mean ± s: age 27.1 ± 4.8 years, [Vdot]O2max 63.7 ± 4.9 ml · min?1 · kg?1) performed four sub-maximal (~70%[Vdot]O2max) and maximal tests with and without different compression stockings, tights, and whole-body compression suits. Arterial lactate concentration, oxygen saturation and partial pressure, pH, oxygen uptake, and ratings of muscle soreness were recorded before, during, and after all tests. In addition, we assessed time to exhaustion. Sub-maximal (P = 0.22) and maximal oxygen uptake (P = 0.26), arterial lactate concentration (P = 0.16; 0.20), pH (P = 0.23; 0.46), oxygen saturation (P = 0.13; 0.26), and oxygen partial pressure (P = 0.09; 0.20) did not differ between the types of clothing (effect sizes = 0.00–0.45). Ratings of perceived exertion (P = 0.10; 0.15), muscle soreness (P = 0.09; 0.10) and time to exhaustion (P = 0.16) were also unaffected by the different clothing (effect sizes = 0.28–0.85). This was the first study to evaluate the effect on endurance performance of different types of compression clothing with increasing amounts of compressive surface. Overall, there were no performance benefits when using the compression garments.  相似文献   
98.
Harold Maurice Abrahams (1899–1978) – the British-Jewish athlete made famous by the film Chariots of Fire – won gold for Britain in the 100 m sprint in the 1924 Paris Olympics. Far from being the ‘outsider’ depicted in Chariots of Fire, however, Abrahams’ ‘Anglicisation’ was extensive and played an important role in his life before, during and after his athletics career. Abrahams’ integration went hand-in-hand with his sporting success – something which was celebrated by British Jewry. Such was his assimilation, that by 1936 – a year when Abrahams courted controversy over his stance on the Berlin Olympics – he was criticised for having ‘lost’ all attachment to the community of his birth. In contrast to the film, where Abrahams is seen to be ‘too Semitic’, the Bedford athlete was actually ‘thoroughly Anglicised’. A desire to move into or support middle-to-upper class British society characterised Abrahams’ personal and sporting life much more so than his Jewishness. As time progressed, Abrahams’ Jewish origins meant less and less, both to Harold himself and to those around him.  相似文献   
99.
This study tackles the birth and development of the sports press in Spain from 1865 to 1899, linked to the need of a bourgeois society to emulate the English lifestyle, characterised by the sports craze. The sports press in Spain fitted extremely well in the late nineteenth century, encouraged by the Regenerationist movement. This is clear by the growth in number of sports publications, by the promotion of physical culture by Regenerationism and by the use of such publications to spread Regenerationism's approach to sport. Both primary and secondary sources were used in the research process. With regard to primary sources, archives containing specific documentation on the origins and early years of the sports press in Spain were examined. A total of 85 sports publications were counted in 18 different towns, but mostly concentrated in Madrid (28) and Barcelona (24). The most widely represented sports in these were cycling (25) and hunting (18). Among those publications that were not specific to one sport, 13 titles included the English-language term ‘sport’, and only two incorporated the newly coined Spanish word, ‘deporte’. Los Deportes (1897–1910) is the most important publication of this period and the foundation stone of modern sports journalism in Spain.  相似文献   
100.
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   
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