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We examined the supposition that swimmers may exhibit an imbalance in bilateral arm power output during simulated swimming exercise. Ten competitive front crawl swimmers (5 males, 5 females; age 20.5+/-2.3 years; height 1.74+/-0.09 m; body mass 72.0+/-16.7 kg; 400 m freestyle swim time 278+/-20.5 s; mean +/- s) performed four incremental (10 W x min(-1)) swim ramp tests on a computer-interfaced biokinetic swim bench ergometer. External power output from each arm was measured continuously to exhaustion. The results showed that, throughout the course of the simulated swim, external power output clearly favoured the left arm (F1,9 = 12.5, P= 0.006). This was especially evident in the final 30 s to exhaustion, when 54.0+/-3.87% of external power output was derived from the left arm versus 46.0+/-3.87% from the right arm. The disparity in external power output was further highlighted when the participants were grouped into unilateral and bilateral breathers. Unilateral breathers (n = 5) produced 57.1+/-2.62% of external power output from the left armversus 42.9+/-2.62% from the right arm (P= 0.001). Bilateral breathers (n = 5) exhibited a more balanced external power output of 51.0+/-1.82% from the left arm and 49.0+/-1.82% from the right arm (P = 0.177). Evidence of power imbalance in the simulated swimming stroke may have important implications for optimizing swim performance. The observed power imbalance may be reduced when a bilateral breathing technique is adopted. 相似文献
137.
This column reports the results of a survey conducted of medical librarian participants in medical informatics training at the University of Pittsburgh. This small study was undertaken in order to identify issues in training different kinds of library and information science practitioners in medical informatics. 相似文献
138.
Other Index
Index to Volume XLI 相似文献139.
The development of services provided by the National Library of Medicine (NLM), which dates back to 1836, is described. MEDLINE, a database of 10-plus million references and abstracts to the world's biomedical literature, was put on the World Wide Web for free searching in 1997 as a system called PubMed, whose use has grown to over 250 million searches per year. PubMed features a variety of links between MEDLINE references and related information – full-text journal articles, DNA sequence data, medical knowledge bases, etc. – at websites within and outside NLM. PubMed is a major component of a larger NLM system, Entrez, which integrates access to a number of genome-related databases with linking features similar to those of PubMed. The newest linked service, which became a reality in February 2000, is PubMed Central, the National Institutes of Health's free repository for primary research reports in all the life sciences. 相似文献
140.
The aim of this study was to assess the influence of three imposed crank rates on the attainment of peak oxygen consumption (VO2peak) and other physiological responses during incremental arm crank ergometry. Twenty physically active, although non-specifically trained, males volunteered for the study. They completed an exercise protocol using an electrically braked arm ergometer (Lode Angio, Groningen, Netherlands) at crank rates of 60, 70 and 80 rev x min(-1). The order of tests was randomized and they were separated by at least 2 days. Peak VO2 was significantly higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Peak ventilation volume increased as a function of crank rate and was higher (P < 0.05) at 80 than at 60 rev x min(-1). Peak heart rate was higher (P < 0.05) at 70 and 80 rev x min(-1) than at 60 rev x min(-1). Furthermore, 70 and 80 rev x min(-1) resulted in an extended test time compared with 60 rev x min(-1). The greater physiological responses observed during the tests at the two faster crank rates might have been the result of a postponement of acute localized neuromuscular fatigue, allowing for more work to be completed. We recommend, therefore, that an imposed crank rate between 70 and 80 rev x min(-1) should be used to elicit VO2peak and other physiological responses in arm crank ergometry. 相似文献