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1.
Energy balance and body composition in sports and exercise 总被引：2，自引：0，他引：2
Loucks AB 《Journal of sports sciences》2004,22(1):1-14
Many athletes, especially female athletes and participants in endurance and aesthetic sports and sports with weight classes, are chronically energy deficient. This energy deficiency impairs performance, growth and health. Reproductive disorders in female athletes are caused by low energy availability (defined as dietary energy intake minus exercise energy expenditure), perhaps specifically by low carbohydrate availability, and not by the stress of exercise. These reproductive disorders can be prevented or reversed by dietary supplementation in compensation for exercise energy expenditure without any moderation of the exercise regimen. Energy balance is not the objective of athletic training. To maximize performance, athletes strive to achieve an optimum sport-specific body size, body composition and mix of energy stores. To pursue these objectives, athletes need to manage fat, protein and carbohydrate balances separately, but it is impractical for athletes to monitor these balances directly, and appetite is not a reliable indicator of their energy and macronutrient needs. To guide their progress, athletes need to eat by discipline and to monitor specific, reliable and practical biomarkers of their objectives. Skinfolds and urinary ketones may be the best biomarkers of fat stores and carbohydrate deficiency, respectively. Research is needed to identify and validate these and other markers. 相似文献
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文章以当前运动营养研究成果为理论基础,使用复合营养物质,通过纯肌酸、谷氨酰胺、强化多肽片和运动饮料的组合,充分发挥复合营养素的协同作用,达到从整体上提高训练效果的目的。举重、皮划艇项目运动员进行运动营养组合调控5—6周后,运动员体脂百分率降低,在不明显增加体重的情况下,肌肉量增加,承受大负荷训练能力提高,减轻大负荷训练... 相似文献
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Contemporary training for power sports involves diverse routines that place a wide array of physiological demands on the athlete. This requires a multi-faceted nutritional strategy to support both general training needs--tailored to specific training phases--as well as the acute demands of competition. Elite power sport athletes have high training intensities and volumes for most of the training season, so energy intake must be sufficient to support recovery and adaptation. Low pre-exercise muscle glycogen reduces high-intensity performance, so daily carbohydrate intake must be emphasized throughout training and competition phases. There is strong evidence to suggest that the timing, type, and amount of protein intake influence post-exercise recovery and adaptation. Most power sports feature demanding competition schedules, which require aggressive nutritional recovery strategies to optimize muscle glycogen resynthesis. Various power sports have different optimum body compositions and body weight requirements, but increasing the power-to-weight ratio during the championship season can lead to significant performance benefits for most athletes. Both intra- and extracellular buffering agents may enhance performance, but more research is needed to examine the potential long-term impact of buffering agents on training adaptation. Interactions between training, desired physiological adaptations, competition, and nutrition require an individual approach and should be continuously adjusted and adapted. 相似文献
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Strength and power athletes are primarily interested in enhancing power relative to body weight and thus almost all undertake some form of resistance training. While athletes may periodically attempt to promote skeletal muscle hypertrophy, key nutritional issues are broader than those pertinent to hypertrophy and include an appreciation of the sports supplement industry, the strategic timing of nutrient intake to maximize fuelling and recovery objectives, plus achievement of pre-competition body mass requirements. Total energy and macronutrient intakes of strength-power athletes are generally high but intakes tend to be unremarkable when expressed relative to body mass. Greater insight into optimization of dietary intake to achieve nutrition-related goals would be achieved from assessment of nutrient distribution over the day, especially intake before, during, and after exercise. This information is not readily available on strength-power athletes and research is warranted. There is a general void of scientific investigation relating specifically to this unique group of athletes. Until this is resolved, sports nutrition recommendations for strength-power athletes should be directed at the individual athlete, focusing on their specific nutrition-related goals, with an emphasis on the nutritional support of training. 相似文献
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Claudia R. Juzwiak Maria S. S. Vitalle Marcelo M. Pinheiro Vera L. Szejnfeld 《Journal of sports sciences》2013,31(11):1209-1217
Abstract In this cross-sectional study, we evaluated the body composition and dietary intake of 44 adolescent tennis players. After being divided into two groups (age 10–13 years and age 14–18), the players had their weight, height, and sexual maturation assessed. Dual-energy X-ray absorptiometry was used to assess body composition. Food intake was obtained from a non-consecutive 4-day food record. The data were analysed using the Virtual Nutri v.1.0 software and compared with the present recommendations for adolescent athletes or dietary reference intakes. Body mass index and body fat for tennis practice were adequate for 89% and 71% of the tennis players respectively, regardless of age group. A calorie deficit greater than 10% of energy expenditure was observed in 32% of the sample. Fifty percent of the athletes consumed carbohydrates in accordance with recommended values. Protein and lipid intakes were above recommended values, while fibre, calcium, potassium, magnesium, and folic acid intakes were below recommendation for 98%, 80%, 100%, 100%, and 98% of the tennis players respectively. The observed nutritional deficiencies represent an additional barrier for adolescents engaged in competitive sports to achieve an optimum nutrition to maintain growth, health, and performance. 相似文献
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Juzwiak CR Amancio OM Vitalle MS Pinheiro MM Szejnfeld VL 《Journal of sports sciences》2008,26(11):1209-1217
In this cross-sectional study, we evaluated the body composition and dietary intake of 44 adolescent tennis players. After being divided into two groups (age 10-13 years and age 14-18), the players had their weight, height, and sexual maturation assessed. Dual-energy X-ray absorptiometry was used to assess body composition. Food intake was obtained from a non-consecutive 4-day food record. The data were analysed using the Virtual Nutri v.1.0 software and compared with the present recommendations for adolescent athletes or dietary reference intakes. Body mass index and body fat for tennis practice were adequate for 89% and 71% of the tennis players respectively, regardless of age group. A calorie deficit greater than 10% of energy expenditure was observed in 32% of the sample. Fifty percent of the athletes consumed carbohydrates in accordance with recommended values. Protein and lipid intakes were above recommended values, while fibre, calcium, potassium, magnesium, and folic acid intakes were below recommendation for 98%, 80%, 100%, 100%, and 98% of the tennis players respectively. The observed nutritional deficiencies represent an additional barrier for adolescents engaged in competitive sports to achieve an optimum nutrition to maintain growth, health, and performance. 相似文献
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Olympic combat sports separate athletes into weight divisions, in an attempt to reduce size, strength, range and/or leverage disparities between competitors. Official weigh-ins are conducted anywhere from 3 and up to 24?h prior to competition ensuring athletes meet weight requirements (i.e. have ‘made weight’). Fighters commonly aim to compete in weight divisions lower than their day-to-day weight, achieved via chronic and acute manipulations of body mass (BM). Although these manipulations may impair health and absolute performance, their strategic use can improve competitive success. Key considerations are the acute manipulations around weigh-in, which differ in importance, magnitude and methods depending on the requirements of the individual combat sport and the weigh-in regulations. In particular, the time available for recovery following weigh-in/before competition will determine what degree of acute BM loss can be implemented and reversed. Increased exercise and restricted food and fluid intake are undertaken to decrease body water and gut contents reducing BM. When taken to the extreme, severe weight-making practices can be hazardous, and efforts have been made to reduce their prevalence. Indeed some have called for the abolition of these practices altogether. In lieu of adequate strategies to achieve this, and the pragmatic recognition of the likely continuation of these practices as long as regulations allow, this review summarises guidelines for athletes and coaches for manipulating BM and optimising post weigh-in recovery, to achieve better health and performance outcomes across the different Olympic combat sports. 相似文献
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Muslim athletes should fast from sunrise to sunset each day throughout the 30 days of Ramadan. Most athletes will continue to train throughout Ramadan, and they may also be required to compete at this time, but they will also engage in the religious, cultural, and social activities that Ramadan represents. The available evidence indicates that high-level athletes can maintain performance during Ramadan if physical training, food and fluid intake, and sleep are appropriate and well controlled. Individualized monitoring of athletes may help to prevent fatigue and overtraining and to reduce the risk of consequent illness and injury. The timing and intensity of training may require adjustment to optimize the training response, and training close to or after sunset may have advantages, but this will vary between individual and team sports and between environments that are predominantly Muslim and those that are predominantly non-Muslim. Training late in the day allows nutrition interventions after training to promote adaptations to the training stimulus, to promote recovery, and might help to reduce muscle damage. Sleep deficits have a number of adverse effects on well-being and performance, and athletes should ensure adequate sleep throughout Ramadan. In non-Muslim majority environments, especially in team sports, coaches and athletes should be sensitive to the needs of their team-mates who may be fasting. Event organizers should take account of the needs of Muslim athletes when scheduling the dates and timings of sports competitions. 相似文献
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The use of dieting, rapid weight loss, and frequent weight fluctuation among athletes competing in weight-class and leanness sports have been considered a problem for years, but the extent of the problem and the health and performance consequences have yet to be fully examined. Most studies examining these issues have had weak methodology. However, results from this review indicate that a high proportion of athletes are using extreme weight-control methods and that the rules of some sports might be associated with the risk of continuous dieting, energy deficit, and/or use of extreme weight-loss methods that can be detrimental to health and performance. Thus, preventive strategies are justified for medical as well as performance reasons. The most urgent needs are: (1) to develop sport-specific educational programmes for athletic trainers, coaches, and athletes; (2) modifications to regulations; and (3) research related to minimum percentage body fat and judging patterns. 相似文献
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Background In many sports, athletes with low body weight and/or low body fat content have a distinct advantage over their opponents. Such an advantage can easily turn into a noticeable disadvantage because low body weight and ' leanness' may also be associated with health problems. 相似文献
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Jeukendrup AE 《Journal of sports sciences》2011,29(Z1):S91-S99
Endurance sports are increasing in popularity and athletes at all levels are looking for ways to optimize their performance by training and nutrition. For endurance exercise lasting 30 min or more, the most likely contributors to fatigue are dehydration and carbohydrate depletion, whereas gastrointestinal problems, hyperthermia, and hyponatraemia can reduce endurance exercise performance and are potentially health threatening, especially in longer events (>4 h). Although high muscle glycogen concentrations at the start may be beneficial for endurance exercise, this does not necessarily have to be achieved by the traditional supercompensation protocol. An individualized nutritional strategy can be developed that aims to deliver carbohydrate to the working muscle at a rate that is dependent on the absolute exercise intensity as well as the duration of the event. Endurance athletes should attempt to minimize dehydration and limit body mass losses through sweating to 2-3% of body mass. Gastrointestinal problems occur frequently, especially in long-distance races. Problems seem to be highly individual and perhaps genetically determined but may also be related to the intake of highly concentrated carbohydrate solutions, hyperosmotic drinks, as well as the intake of fibre, fat, and protein. Hyponatraemia has occasionally been reported, especially among slower competitors with very high intakes of water or other low sodium drinks. Here I provide a comprehensive overview of recent research findings and suggest several new guidelines for the endurance athlete on the basis of this. These guidelines are more detailed and allow a more individualized approach. 相似文献
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目的:对篮球、手球、足球运动员的身体成分和肌肉力量进行比较分析,探讨三大球运动员身体素质的特点与差异,为运动训练以及运动员科学选材提供理论参考.方法:研究对象均为篮球、足球、手球二级以上专业运动员,均为男性,身高、体重、年龄和运动年限无明显差异,对研究对象进行体成分和肌肉力量测试及比较分析.结果:篮球组与手球组腹下脂肪比率、基础代谢、肥胖程度、BMI以及细胞液都有非常显著性差异(P＜0.01);篮球组与足球组之间下肢和腹下脂肪与体重比存有差异性(P＜0.05),胸下脂肪与体重比存有非常显著性差异(P＜0.01);手球运动员与足球运动员之间肥胖程度、BMI、细胞液和基础代谢均有非常显著性差异(P＜0.01);在上下肢力量方面篮球运动员与手球和足球运动员存有非常显著性差异(P＜0.01).结论:手球运动员在身高、体重、脂肪比率、BMI、细胞量、蛋白质、无机盐、细胞液方面都明显高于篮球和足球运动员;篮球运动员在力量方面比较占据优势;足球运动员身材相对较小,在体脂比率、BMI以及上下肢力量方面低于篮球和手球运动员. 相似文献
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“女运动员三联征”包括了相互联系的三个征象，即进食障碍、闭经和早发骨质疏松。这三种症状在女运动员经常同时出现，尤其易发生在那些从事美学和生理学上依赖低体脂或低体重取得成功的项目的运动员中，是影响女运动员健康和竞技状态的重要因素。女运动员三联征与机体能量不平衡有关。从机体能量平衡调节的角度综述女运动员三联征的发生机制。 相似文献
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目的：检测黑龙江省部分中青年干部身体成分,根据存在的问题采取有效的运动干预措施,改善健康状况。方法：受试者清晨空腹状态测试身体成分,对比不同年龄组间身体与生理年龄、体重与标准体重差值。体重指数、体脂肪百分比,进行统计分析,总结存在的问题。结果：黑龙江省中青年干部总体上身体年龄普遍高于生理年龄,各年龄组体重指数高于正常值,各年龄组体脂肪百分比均高于正常值。结论：黑龙江省中青年干部健康状况欠佳,31-35岁年龄组状况最差,各年龄组应通过适宜的运动方式降体重,尤其降脂肪含量。 相似文献
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Houtkooper L Abbot JM Nimmo M;International Association of Athletics Federations 《Journal of sports sciences》2007,25(Z1):S39-S47
Throwers, jumpers, and combined events athletes require speed, strength, power, and a wide variety of technical skills to be successful in their events. Only a handful of studies have assessed the nutritional needs of such athletes. Because of this, recommendations for nutritional requirements to support and enhance training and competition performances for these athletes are made using research findings from sports and exercise protocols similar to their training and competitive events. The goals of the preparation cycle of nutrition periodization for these athletes include attaining desirable body weight, a high ratio of lean body mass to body height, and improving muscular power. Nutritional recommendations for training and competition periods include: (1) meeting energy needs; (2) timing consumption of adequate fluid and electrolyte intakes before, during, and after exercise to promote adequate hydration; (3) timing consumption of carbohydrate intake to provide adequate fuel for energy demands and to spare protein for muscle repair, growth, and maintenance; (4) timing consumption of adequate protein intake to meet protein synthesis and turnover needs; and (5) consuming effective nutritional and dietary supplements. Translating these nutrient and dietary recommendations into guidelines these athletes can apply during training and competition is important for enhancing performance. 相似文献
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江苏省摔跤队膳食营养状况的调查与评价 总被引：1，自引：0，他引：1
研究目的:膳食营养是保证运动员营养素的需要和维持体能的最重要的物质基础,对训练起重要的保证作用,与膳食营养在竞技体育中重要位置不相适应的是运动员膳食的不平衡现象普遍存在,它长期影响训练的效果和训练后的恢复。本研究通过调查备战十运会的江苏省摔跤队的膳食状况,对其做出评估,为平衡膳食提供依据。研究方法:采用食物称重法,称量并记录每个运动员所吃主副食的熟重、剩余重量,计算出所吃食物生重。记录运动员饮水量及营养品服用量,用软件计算出各种营养素摄入量及食物构成。将计算结果与运动员每日膳食营养供给标准,食物摄入供给标准进行比较做出合理评价。研究结果:江苏省摔跤运动员三大营养素的摄入比例多不合理,碳水化合物78%不足,56%的运动员脂肪和蛋白质超过推荐标准。中餐、晚餐的能量摄入比例超标比例较高,早餐不足。运动员各种矿物质摄入都超过推荐值,运动员的维生素摄入相对不足,VA、VC、VB1、VPP不同程度地缺乏。运动员每日的摄入量变化很大,最大幅度可达到83%。运动员进食的多少与运动量、运动强度、饭菜的内容以及个人的喜好有很大的关系。 相似文献
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自20世纪20年代以来,极低碳水化合物饮食或生酮饮食疗法被应用于癫痫的治疗,甚至在某些情况下能够完全取代药物治疗。1970年以后,这种饮食疗法作为一种肥胖治疗手段而被广泛知晓 。生酮饮食（Ketogenic Diets,KD）是指碳水化合物减少（通常小于20 g/d或低于每天摄入总能量的5%）而蛋白质和脂肪含量相对增加的饮食。目前认为这三大营养物质的重排可以诱导生理性酮症,进而减轻体重。近年来,许多运动员也希望通过生酮饮食减脂以取得更好的运动表现。尽管生酮饮食在体重管理方面作用显著,但它是否能够维持或提高体能表现仍不明确。文章讨论了生酮饮食的代谢效应和潜在风险,以及近期关于生酮饮食对体重减轻、肌肉合成和运动表现影响的研究进展。 相似文献
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Burke LM Millet G Tarnopolsky MA;International Association of Athletics Federations 《Journal of sports sciences》2007,25(Z1):S29-S38
The goal of training is to prepare the distance athlete to perform at his or her best during major competitions. Whatever the event, nutrition plays a major role in the achievement of various factors that will see a runner or walker take the starting line in the best possible form. Everyday eating patterns must supply fuel and nutrients needed to optimize their performance during training sessions and to recover quickly afterwards. Carbohydrate and fluid intake before, during, and after a workout may help to reduce fatigue and enhance performance. Recovery eating should also consider issues for adaptation and the immune system that may involve intakes of protein and some micronutrients. Race preparation strategies should include preparation of adequate fuel stores, including carbohydrate loading for prolonged events such as the marathon or 50-km walk. Fluid and carbohydrate intake during races lasting an hour or more should also be considered. Sports foods and supplements of value to distance athletes include sports drinks and liquid meal supplements to allow nutrition goals to be achieved when normal foods are not practical. While caffeine is an ergogenic aid of possible value to distance athletes, most other supplements are of minimal benefit. 相似文献