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171.
In this study, we assessed the influence that pre-exercise glucose ingestion of two concentrations has on the physiological responses of paraplegic athletes. Eight men with paraplegia ingested a drink containing 4% (low) or 11% (high) carbohydrate in a randomized double-blind crossover design, 20 min before exercise. The participants performed wheelchair exercise at 65% of peak oxygen uptake for 1 h followed by a 20 min performance test. During both trials, the physiological responses were similar and indicated steady-state exercise. At the onset of exercise, blood glucose concentrations in both trials increased after carbohydrate ingestion (P < 0.05) before returning to resting values after 20 min of exercise and there were no differences between trials. Free fatty acid concentrations increased from rest to 1 h of exercise in both trials, with a greater increase during the low carbohydrate trial that led to a difference in free fatty acids between trials at the end of the 1 h tests (P < 0.05). There was a tendency for the performance distances and power outputs achieved during the high carbohydrate trial to be greater than those achieved during the low carbohydrate trial (P= 0.08). In conclusion, when paraplegic athletes ingested low and high carbohydrate drinks before exercise, the decline in blood glucose concentrations was similar. The tendency for higher blood glucose concentrations, respiratory exchange ratios and power outputs and lower free fatty acid concentrations (P < 0.05) during the high carbohydrate trial suggests that a higher concentration of carbohydrate in a sports drink might be a better choice for paraplegic athletes. 相似文献
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The purpose of this study was to determine the effect of triathlon training using multiple, short cycle-run sequences (multicycle-run training) on cycle-run performance. Twelve competitive triathletes, randomized into two groups, underwent multicycle-run training or normal training for 6 weeks. During this period, baseline training remained the same for both groups, and only the high-intensity component differed. The differentiated exercises were performed at or above 100% maximal aerobic velocity. The improvements in overall cycle-run performance were similar (3.3 +/- 1.4 % and 6.1 +/- 1.7% rise in Performance in multicycle-run and normal training, respectively). However, the improvement in performance was significantly greater for the multicycle-run training (-11.2 +/- 6.8 s versus -1.2 +/- 7. 7 s for multicycle-run training and normal training, respectively) during both the cycle-run change and the first 333-m lap, which together are termed the cycle-run transition. We concluded that 6 weeks of multicycle-run training did not induce greater improvement in cycle-run performance than did normal training in competitive triathletes. However, it did induce significant improvement in the cycle-run transition. This finding indicates that multicycle-run training may help competitive triathletes to develop greater skill and better physiological adaptations during this critical transition period of the triathlon race. 相似文献
176.
Science and the state in modern China 总被引:1,自引:0,他引:1
177.
Groundwater recharge significantly affects soil moisture redistribution through capillary rise. In this study,the soil matric potential at depths of 5, 10, 20 and 30 cm above the groundwater tables of 10, 30 and 60 cm were measured for 5 d. Soil hydraulic properties were analyzed by using the Philips and de Vries model. Results showed that evaporation mainly influenced the matric potential of the shallow layer at the 5 cm depth regardless of the saturation of the layer. Groundwater recharge mainly affected soil moisture at the depth of 20 cm or more. A constant matric potential layer existed between the evaporation front and capillary rise front where moisture content did not change.The isothermal-liquid hydraulic conductivity(KLh) and the thermal-vapor hydraulic conductivity(Kv T) were the dominant hydraulic conductivities in the liquid and vapor phases. At the groundwater table depths of 10, 30 and 60 cm,the mean peak values of KLh were 2.32×10-7, 1.63×10-7 and 0.29×10-7 m/s, respectively, whereas the mean peak values of K-v T were 2.7×107, 2.4×10-7 and 1.8 ×10-7m/s, respectively. 相似文献
178.
昆士兰大学图书馆空间价值评估实践及启示 总被引:1,自引:0,他引:1
分析了图书馆空间价值评估的必要性,介绍了澳大利亚昆士兰大学图书馆空间价值评估实践、意义以及对国内图书馆空间价值优化的启示。 相似文献
179.
赵林 《语数外学习(高中版)》2014,(4):22
正我们知道,目标教学法最大的优势是能避免教学中的随意性,能使学生思路清晰,目标明确地完成学习任务。但我们不能把目标教学法简单化。笔者认为,目标的确立至关重要,就像战场上的指挥员,只有定准目标才能率领战士们冲锋陷阵,勇往直前,去夺取胜利。如果指挥员目标方向搞错了,就会贻误战机,造成损失,甚至全军覆没。教学中的目标就像指挥棒,它牵制着师生的行动,因而务必不 相似文献
180.
正Pre-reading task1.How many reality television shows can you name?2.Which shows do you watch?Now read this review of the reality television show Supernanny.A Review of Supernanny I don’t usually like reality television shows but I’m completely hooked on the programme Supernanny.It’s an excellent show,which basically fi lms a family who are having problems dealing with their naughty children. 相似文献