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191.
All traumatic and overuse injuries occurring during an average period of 4 years (2002/09) in a group of 51 currently active road top-level cyclists were retrospectively registered through clinical interviews. Average age was 25.8 years. Average training and competition period was 28.3 ± 2.4 h a week. Only 8 cyclists (15.6%) were completely free from lesions during the period of study. The remaining 43 cyclists suffered a total of 112 lesions; however, 9 out of these were unrelated to their cycling practice. These 103 cycling-related injuries include 50 (48.5%) traumatic and 53 (51.5%) overuse injuries. Twenty-eight fractures were reported, the clavicle being the most frequently affected bone (11 cases). The 68.5% of overuse injuries were located in the lower limbs. Most overuse injuries (89.6%) occurred during the training period. According to the injury abbreviated scale (AIS), severe lesions were only found in 4 cases (8% of traumatic injuries). Overall injury rates were 0.50 per racer/year, 2.02 per studied racer, and 0.007 per 1000 km of training and competition. Active professional top-level cyclists are exposed to a high injury risk. According to the scarce previously published data the current study provides relevant information on the injury occurrence of still active top-level road cycling. 相似文献
192.
Abstract In soccer, critical match events like goal attempts can be preceded by periods of instability in the balance between the two teams' behaviours. Therefore, we determined periods of high variability in the distance between the teams' centroid positions longitudinally and laterally in an international-standard soccer match and evaluated corresponding match events. Position data were collected with AMISCO Pro?. Inter-team distance variability was calculated over a 3-s moving window. Out of the 242 match periods that exceeded the variability criterion, 51 were dead-ball situations. Match events identified through longitudinal inter-team distance primarily related to defending players moving forward-backward after a longitudinal pass. Match events identified through lateral inter-team distance mainly corresponded with defending players moving laterally following sideways passing. One of two goals and two of fourteen goal-attempts were preceded by a period of high variability. Together, periods of highly variable inter-team distance were associated with collective defensive actions and team reorganisation in dead-ball moments rather than goals or goal attempts. Inter-team dynamics quantified (mutual) reorganisation of the teams and marked teams' collective defensive ability to respond to attacking explorations. 相似文献
193.
Knechtle B Knechtle P Wirth A Alexander Rüst C Rosemann T 《Journal of sports sciences》2012,30(11):1131-1140
In 219 recreational male runners, we investigated changes in body mass, total body water, haematocrit, plasma sodium concentration ([Na(+)]), and urine specific gravity as well as fluid intake during a 100-km ultra-marathon. The athletes lost 1.9 kg (s = 1.4) of body mass, equal to 2.5% (s = 1.8) of body mass (P < 0.001), 0.7 kg (s = 1.0) of predicted skeletal muscle mass (P < 0.001), 0.2 kg (s = 1.3) of predicted fat mass (P < 0.05), and 0.9 L (s = 1.6) of predicted total body water (P < 0.001). Haematocrit decreased (P < 0.001), urine specific gravity (P < 0.001), plasma volume (P < 0.05), and plasma [Na(+)] (P < 0.05) all increased. Change in body mass was related to running speed (r = -0.16, P < 0.05), change in plasma volume was associated with change in plasma [Na(+)] (r = -0.28, P < 0.0001), and change in body mass was related to both change in plasma [Na(+)] (r = -0.36) and change in plasma volume (r = 0.31) (P < 0.0001). The athletes consumed 0.65 L (s = 0.27) fluid per hour. Fluid intake was related to both running speed (r = 0.42, P < 0.0001) and change in body mass (r = 0.23, P = 0.0006), but not post-race plasma [Na(+)] or change in plasma [Na(+)] (P > 0.05). In conclusion, faster runners lost more body mass, runners lost more body mass when they drank less fluid, and faster runners drank more fluid than slower runners. 相似文献
194.
Shen B Reinhart-Lee T Janisse H Brogan K Danford C Jen KL 《Research quarterly for exercise and sport》2012,83(2):168-174
The purpose of this study was to describe the physical activity levels of urban inner city preschoolers while attending Head Start, the federally funded preschool program for children from low-income families. Participants were 158 African American children. Their physical activity during Head Start days was measured using programmed RT-3 accelerometers. Results revealed that the children spent the most time in sedentary and light physical activity, while their participation in moderate-to-vigorous physical activities was low. Given the sedentary class format and limited physical space for the Head Start programs observed, we suggest adding a structured physical activity component to Head Start schools to fight the overweight and obesity crisis. 相似文献
195.
196.
小莫莫从未打算离开双鱼星。
自从决定做双鱼星的守望者后,她就准备和桃乐丝乖乖地待在这颗美丽的星球上。这里有山有水,有花有草,也有可爱的小动物,但这里只有她和桃乐丝两个人。所以,这是颗孤独的星球。幸好小莫莫是耐得住寂寞的,但桃乐丝不是。 相似文献
197.
各位2006级的同学们,我很高兴,能与沙利文院长一起在这儿欢迎你们来到耶鲁大学。我也要向一起参加典礼的家长及亲友们表示诚挚的欢迎,尤其要感谢这些家长们,感谢你们把这些才华横溢、充满希望的孩子委托给耶鲁,他们将在耶鲁度过美好的大学时光。 相似文献
198.
199.
Despite the ubiquity and critical importance of science and technology in international affairs, their role receives insufficient
attention in traditional international relations curricula. There is little literature on how the relations between science,
technology, economics, politics, law and culture should be taught in an international context. Since it is impossible even
for scientists to master all the branches of natural science and engineering that affect public policy, the learning goals
of students whose primary training is in the social sciences should be to get some grounding in the natural sciences or engineering,
to master basic policy skills, to understand the basic concepts that link science and technology to their broader context,
and to gain a respect for the scientific and technological dimensions of the broader issues they are addressing. They also
need to cultivate a fearless determination to master what they need to know in order to address policy issues, an open-minded
but skeptical attitude towards the views of dueling experts, regardless of whether they agree with their politics, and (for
American students) a world-view that goes beyond a strictly U.S. perspective on international events. The Georgetown University
program in Science, Technology and International Affairs (STIA) is a unique, multi-disciplinary undergraduate liberal arts
program that embodies this approach and could be an example that other institutions of higher learning might adapt to their
own requirements. 相似文献
200.
Existing data indicate that newborns are able to recognize individual faces, but little is known about what perceptual cues drive this ability. The current study showed that either the inner or outer features of the face can act as sufficient cues for newborns' face recognition (Experiment 1), but the outer part of the face enjoys an advantage over the inner part (Experiment 2). Inversion of the face stimuli disrupted recognition when only the inner portion of the face was shown, but not when the whole face was fully visible or only the outer features were presented (Experiment 3). The results enhance our picture of what information newborns actually process and encode when they discriminate, learn, and recognize faces. 相似文献