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951.
In this study, we examined the effects of upper-body pre-cooling before intermittent sprinting exercise in a moderate environment. Seven male and three female trained cyclists (age 26.8+/-5.5 years, body mass 68.5+/-9.5 kg, height 1.76+/-0.13 m, V O2peak 59.0+/-11.4 mL. kg(-1). min(-1); mean+/-s) performed 30 min of cycling at 50% V O2peak interspersed with a 10-s Wingate cycling sprint test at 5 min intervals. The exercise was performed in a room controlled at 22 degrees C and 40% relative humidity. In the control session, the participants rested for 30 min before exercise. In the pre-cooling session, the participants wore the upper segment of a liquid conditioning garment circulating 5 degrees C coolant until rectal temperature decreased by 0.5 degrees C. Rectal temperature at the start of exercise was significantly lower in the pre-cooling (36.5+/-0.3 degrees C) than in the control condition (37.0+/-0.5 degrees C), but this difference was reduced to a non-significant 0.4 degrees C throughout exercise. Mean skin temperature was significantly lower in the pre-cooling (30.7+/-2.3 degrees C) than in the control condition (32.5+/-1.6 degrees C) throughout exercise. Heart rate during submaximal exercise was similar between the two conditions, although peak heart rate after the Wingate sprints was significantly lower in the pre-cooling condition. With pre-cooling, mean peak power (909+/-161 W) and mean overall power output (797+/-154 W) were similar to those in the control condition (peak 921+/-163 W, mean 806+/-156 W), with no differences in the subjective ratings of perceived exertion. These results suggest that upper-body pre-cooling does not provide any benefit to intermittent sprinting exercise in a moderate environment. 相似文献
952.
In this study, we assessed the agreement between the powers recorded during a 30 s upper-body Wingate test using three different methods. Fifty-six men completed a single test on a Monark 814E mechanically braked ergometer fitted with a Schoberer Rad Messtechnik (SRM) powermeter. A commercial software package (Wingate test kit version 2.21, Cranlea, UK) was used to calculate conventional and corrected (with accelerative forces) values of power based on a resistive load (5% body mass) and flywheel velocity. The SRM calculated powers based on torque (measured at the crank arm) and crank rate. Values for peak 1 and 5 s power and mean 30 s power were measured. No significant differences (P >0.05) were found between the three methods for 30 s power values. However, the corrected values for peak 1 and 5 s power were 36 and 23% higher (P <0.05) respectively than those for the conventional method, and 27 and 16% higher (P <0.05) respectively than those for the SRM method. The conventional and SRM values for peak 1 and 5 s power were similar (P >0.05). Power values recorded using each method were influenced by sample time (P <0.05). Our results suggest that these three measures of power are similar when sampled over 30 s, but discrepancies occur when the sample time is reduced to either 1 or 5 s. 相似文献
953.
Urquhart C Chambers M Connor S Lewis L Murphy J Roberts R Thomas R 《Health information and libraries journal》2002,19(3):146-157
The aim of the article is to review evaluations of distance learning programmes in health information management, in order to identify the critical success factors for such programmes and discuss future directions. The emphasis is on the UK experience, based partly on reflections on the experience of one programme at University of Wales Aberystwyth (now over 10 years old), and partly on a policy review conducted for the NHS Information Authority and the NHS Information Policy Unit. The methods are, as far as possible, those of a systematic review of existing research, with, additionally, an overview of relevant policy developments for lifelong learning. The topics covered include the aims, objectives and educational philosophies of the programmes. The evidence, combined with the UWA experience, indicates the importance of face-to-face interaction, to complement distance or virtual learning. A student-centred approach to curriculum design and delivery is essential. 相似文献
954.
Jamurtas AZ Goldfarb AH Chung SC Hegde S Marino C Fatouros IG 《Journal of sports sciences》2001,19(12):931-935
The aim of this study was to determine whether beta-endorphin infusion influences liver or muscle glycogen concentration during exercise. Thirty-two rats (Harlan Co., IN, USA) with a body mass of 265-290 g were assigned at random to four groups, each of eight rats: (1) beta-endorphin infusion for 90 min at rest; (2) beta-endorphin infusion for 90 min while running on a rodent treadmill at 22 m x min(-1) and 0% grade; (3) saline infusion (0.9% NaCl) for 90 min at rest; and (4) saline infusion for 90 min while running on a rodent treadmill at 22 m x min(-1) and 0% grade. Beta-endorphin infusion elevated plasma beta-endorphin concentration by 2.5-fold at rest compared with saline infusion at rest, and by two-fold after exercise compared with saline infusion after exercise. Beta-endorphin infusion attenuated exercise-induced glucose concentration but did not alter the fasting hepatic glycogen concentration at rest or after exercise compared with saline infusion. Fasting hepatic glycogen decreased significantly as a result of 90 min of exercise independent of treatment. Deep intermedius muscle glycogen concentration at rest was similar after 90 min of both beta-endorphin and saline infusion and decreased significantly as a result of 90 min of exercise independent of treatment. Our results suggest that liver and muscle glycogenolysis is not responsible for the differences in plasma glucose with beta-endorphin infusion during exercise. 相似文献
955.
OBJECTIVE: The study assessed the coping strategies of MEDLIB-L subscribers during an unexpected disruption in the list's service. METHODS: An online survey of MEDLIB-L subscribers was performed following a six-day service outage in August 1999. RESULTS: Respondents' information needs resulted in two distinct coping strategies. Subscribers without a recognized information need or an information need determined to be not pressing coped by waiting out the interruption. Subscribers with pressing information needs turned to alternative methods of resolving these needs. CONCLUSIONS: While most respondents missed the list and the assistance that it provided, many did not feel that the outage required significant coping strategies. The outage was viewed as a "minor stressor" and did not require secondary-level assessment of the availability and suitability of alternative resources. 相似文献
956.
A landmark-based statistical method, morphological variation analysis, for the quantification of the repeatability in the arrangement of body segments during the execution of sport actions has recently been developed. A two-dimensional shape is produced and its morphology is studied. The method was used to measure the within-team variability of the relative positions of players during the execution of offensive schemes in soccer. Two junior soccer teams of different technical abilities (semi-professional vs. amateur), each playing two standardized offensive schemes of different difficulty (easier: throw-in; more difficult: wing attack) were filmed. Each scheme was repeated 25 (semi-professionals) or 10 (amateurs) times. For each repetition, the position of the players in a single significant frame was analysed using morphological variation analysis. The reproducibility of both schemes was higher among the semi-professionals than among the amateurs (two-way analysis of variance, P<0.005). The repeatability of the players' relative positions was related to the difficulty of the scheme and the technical level of the team. Among the amateurs, the throw-in was more reproducible than the wing attack (Student's t-test, P<0.005). The method not only allows the quantification of collective (team) coordination, but also the separation of the influence of individual players. 相似文献
957.
Academic health sciences libraries in the United States and Canada were surveyed regarding collection development trends, including their effect on approval plan and blanket order use, and use of outsourcing over the past four years. Results of the survey indicate that serials market forces, budgetary constraints, and growth in electronic resources purchasing have resulted in a decline in the acquisition of print items. As a result, approval plan use is being curtailed in many academic health sciences libraries. Although use of blanket orders is more stable, fewer than one-third of academic health sciences libraries report using them currently. The decline of print collections suggests that libraries should explore cooperative collection development of print materials to ensure access and preservation. The decline of approval plan use and the need for cooperative collection development may require additional effort for sound collection development. Libraries were also surveyed about their use of outsourcing. Some libraries reported outsourcing cataloging and shelf preparation of books, but none reported using outsourcing for resource selection. The reason given most often for outsourcing was that it resulted in cost savings. As expected, economic factors are driving both collection development and outsourcing practices. 相似文献
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