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1.
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
2.
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
3.
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
4.
Meyer F O'Connor H Shirreffs SM;International Association of Athletics Federations 《Journal of sports sciences》2007,25(Z1):S73-S82
Athletics is a popular sport among young people. To maintain health and optimize growth and athletic performance, young athletes need to consume an appropriate diet. Unfortunately, the dietary intake of many young athletes follows population trends rather than public health or sports nutrition recommendations. To optimize performance in some disciplines, young athletes may strive to achieve a lower body weight or body fat content and this may increase their risk for delayed growth and maturation, amenorrhoea, reduced bone density, and eating disorders. Although many of the sports nutrition principles identified for adults are similar to those for young athletes, there are some important differences. These include a higher metabolic cost of locomotion and preferential fat oxidation in young athletes during exercise. Young athletes, particularity children, are at a thermoregulatory disadvantage due to a higher surface area to weight ratio, a slower acclimatization, and lower sweating rate. An appropriate dietary intake rather than use of supplements (except when clinically indicated) is recommended to ensure young athletes participate fully and safely in athletics. 相似文献
5.
《Sport Management Review》2019,22(1):68-79
There has been a rise in sport-focused event management organisations staging increasingly challenging quests for amateur athletes. Whilst endeavours such as running a marathon or completing an Ironman triathlon were previously pinnacle achievements for amateur athletes, sporting hyperchallenges, events covering greater distances, crossing more difficult terrain, or posing more extreme challenges have set the performance bar significantly higher. Cast against Western neoliberal backdrops the ever-expanding supply-side of this market is broadening opportunities for amateur athletes to test their physical limits, thus necessitating investment of inordinate personal resources. Simultaneously, there is growing empirical and anecdotal evidence suggesting unfavourable impacts can flow from intensely pursuing extreme endurance sports including impacts to athletes’ health and relationships. The authors draw upon intertwined theories of business ethics and corporate social responsibility to critique business practices of sport-focused event management organisations delivering sporting hyperchallenges. The authors propose a conceptual framework aimed at encouraging future research into potential health, social, and fiscal implications stemming from this complex, unregulated market. 相似文献
6.
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
7.
Sleep is generally regarded as a valuable resource for psychological and physiological well-being. Although the effects of sleep on athletic performance have been acknowledged in sport science, few studies have investigated the prevalence of sleep problems and their effects on elite athletes before a sport event. In this study, 632 German athletes from various sports were asked about their sleep habits during the night(s) before an important competition or game. The findings indicate that 65.8% of the athletes experienced poor sleep in the night(s) before a sports event at least once in their lives and a similarly high percentage (62.3%) had this experience at least once during the previous 12 months. Athletes of individual sports reported more sleep difficulties than athletes of team sports. The main sleep problem was not being able to fall asleep. Internal factors such as nervousness and thoughts about the competition were rated highest for causing sleep problems. Most athletes stated that disturbed sleep had no influence on their athletic performance; however, athletes also reported effects such as a bad mood the following day, increased daytime sleepiness, and worse performance in the competition or game. The differences between individual and team sports indicate that athletes in some sports need more help than those in other sports in managing sleep problems. 相似文献
8.
《European Journal of Sport Science》2013,13(4):315-321
AbstractWhile an increasing number of research is devoted to the understanding of placebo effects in sports, athletes' experiences with and attitudes towards the use of placebo for performance enhancement remain poorly understood. In this study, 79 elite athletes from different sports were surveyed on five issues related to placebo use in sports. Results showed that 47% of the athletes have experienced placebo effects in the past. A majority of the athletes (82%) thought that placebos could affect their sports performances. A wider use of placebos in sport settings was endorsed more by those who have experienced placebo effects in the past than those who did not (P = .005). Regardless of past experience with placebo, more than half of the athletes (53%) would accept an unknown but legitimate substance from the coach, and 67% of them would not mind a placebo-linked deception if that was effective. These findings confirm that most elite athletes believe in the power of placebos in enhancing sports performance, and those having a positive past experience exhibit slightly more favourable attitudes in contrast to those without such experiences. 相似文献
9.
极限皮划艇激流回旋是新兴运动,探索运动项目的训练特征是提高竞技水平的基础,提高教练员对训练特征的认知水平是形成正确训练理念的前提。研究运用运动训练学理论,采用文献资料法、问卷调查法和逻辑分析法对我国极限皮划艇激流回旋项目教练员对训练特征的认知进行调查研究,得出结论:绝大部分教练员对极限皮划艇激流回旋项目的技术、战术、体能和心理训练特征的认知符合项目的运动特征和竞赛特征;近4成教练员对该项目训练理念的认知不够清晰;我国极限皮划艇激流回旋项目运动员专项化训练水平较低。建议:加强项目供能结构等的基础研究;加强该项目运动员的专项化训练程度,以尽快提高竞技水平。 相似文献
10.
科学训练、健康传播与奥运的平民化战略 总被引：9，自引：4，他引：5
运动员内稳态的品质表征了健康水平和运动水平。运动训练的平台期对应于运动员的内稳态。运动训练的过程是打破低水平内稳态重建高水平内稳态的过程。竞技训练对运动水平的提高也是对健康水平的提高。内稳态品质的提高至少包括体力和智力两个密切联系的部分,智力提高的空间远远大于体力提高的空间,加强智力开发有助于运动水平的提高和运动寿命的延长。对运动的兴趣和喜好是运动训练的内在奖赏机制。对运动的兴趣越浓,对运动疲劳的忍受能力越强,运动水平的提高和运动寿命的延长就越显著。因此,科学训练的信息应该通过健康传播普及到大众健身活动中,奥运健儿应该在全民健身的基础上选拔。 相似文献
11.
随着国家对体育运动发展支持力度的加大,民俗体育项目得以迅速发展,其中龙舟运动在成为全国竞技运动正式比赛项目后,逐渐在高校发展并具有较大规模。但是竞技龙舟运动在训练或比赛中易导致体育风险事故的发生,或给学生的身心和财产带来严重的损失。本文主要采用文献资料法、问卷调查法、帕累托分析法等研究方法,以高校竞技龙舟运动风险因素为研究对象,以高校竞技龙舟运动员、教练员、裁判员为调查对象,对其龙舟运动的风险情况进行调查与分析,运用帕累托分析法进行数据分析,找出高校竞技龙舟运动风险的主次风险因素,提出对高校竞技龙舟运动的风险防范对策。得出以下结论:(1)高校竞技龙舟运动的主要风险为组织管理因素风险、场地器材因素风险、运动员自身因素风险和教练员的影响因素风险;其他因素风险为次要风险;裁判员的影响因素风险为一般风险。(2)组织管理因素风险主要表现在赛区组织、运动员管理、学校管理方面;场地环境因素风险主要集中在自然环境、龙舟场地、龙舟器材方面;运动员自身因素风险主要体现在运动员的行为活动、心理、知能技能方面。(3)无法去控制体育运动自身不可避免的风险,但可以因地制宜地应对风险,运用预防控制法、风险规避法、风险转移法进行针对各类风险的防范。 相似文献
12.
Valdir De Aquino Lemos Eduardo Da Silva Alves Paulo Adriano Schwingel João Paulo Pereira Rosa Andressa Da Silva Ciro Winckler 《European Journal of Sport Science》2016,16(8):955-964
Body composition is a physiological variable associated with physical activity and, in some cases, is related to athletic performance. Our objectives were to describe the body composition of participants in three distinct Paralympic sports and to compare the values of body density and estimated body fat obtained from the Paralympic athletes on the National Team by air-displacement plethysmography (ADP) and by the anthropometric method (skinfolds (SFs)). The sample consisted of 70 volunteers of both genders. The body composition of the volunteers was evaluated using the ADP in a Bod Pod® and seven SFs. There were no significant differences between the values obtained by ADP and SF for body fat percentage (p?=?.58) and body density (p?=?.49). Analysis by Bland–Altman plots showed mean differences of 0.56?±?4.94 (?9.12–10.23) and ?0.0017?±?0.0113 (?0.024–0.020) for body fat percentage and body density, respectively. In conclusion, body composition analyses of Paralympic athletes by the ADP and SF methods show similar results, and ADP should be used as the first option when available. When the use of ADP is not possible, estimating body density and fat percentage by SF is a viable alternative for Paralympic athletes when future comparisons will use the same analysis method. 相似文献
13.
采用文献资料法、访谈法、比较分析法等方法对我国参加2009年厦门国际马拉松赛的优秀运动员的运动成绩、训练特点进行调查研究。结果表明,马拉松跑的成绩与运动员的年龄、身高、体重、身体质量指数等相关性较低,而与5 000 m、10 000 m和半程马拉松跑的成绩高度相关;与外国运动员相比,我国马拉松运动员采用大强度、大训练量的训练相对较少;应加强力量训练,并高度重视高原训练,这是取得优异运动成绩主要训练方法。 相似文献
14.
《European Journal of Sport Science》2013,13(2):59-72
Abstract Amino acids contribute between 2–8% of the energy needs during endurance exercise. Endurance exercise training leads to an adaptive reduction in the oxidation of amino acids at the same absolute exercise intensity, however, the capacity to oxidize amino acids goes up due to the increase in the total amount of the rate limiting enzyme, branched chain 2-oxo-acid dehydrogenase. There appears to be a modest increase (range?=?12–95%) in protein requirements only for very well trained athletes who are actively training. Although the majority of athletes will have ample dietary protein to meet any increased need, those on a hypoenergetic diet or during extreme periods of physical stress may need dietary manipulation to accommodate the need. Caffeine is a trimethylxanthine derivative that is common in many foods and beverages. The consumption of caffeine (3–7 mg/kg) prior to endurance exercise improves performance for habitual and non-habitual consumers. The ergogenic effect is likely due to a direct effect on muscle contractility and not via an enhancement of fatty acid oxidation. Creatine is important in intra-cellular energy shuttling and in cellular fluid regulation. Creatine monohydrate supplementation (20 g/d X 3–5 days) increases fat-free mass, improves muscle strength during repetitive high intensity contractions and increases fat-free mass accumulation and strength during a period of weight training. Given the increase in weight, there are likely neutral or even performance reducing effects in sports that are influenced by body mass (i.e., running, hill climbing cycling). 相似文献
15.
Dimitrios Challoumas Georgios Dimitrakakis 《Sports biomechanics / International Society of Biomechanics in Sports》2017,16(3):325-341
Infraspinatus atrophy (IA) is much more prevalent in overhead sports compared with the general population. Its exact aetiology in this group of athletes remains unclear and definitive associations with pathology and performance have not yet been reached. The aim of this systematic review is to present the evidence on IA in overhead athletes focussing on the proposed mechanisms of suprascapular neuropathy and its associations with shoulder pathology and performance. A thorough literature search via Medline, EMBASE and Scopus was performed. From the nine articles identified, the majority of authors propose suprascapular nerve (SN) injury at the spinoglenoid notch; however, the suprascapular notch has also been suggested as a potential site of injury. With regard to the exact mechanism of suprascapular neuropathy, the majority of authors propose repeated traction of the nerve during extreme shoulder abduction and horizontal adduction and/or eccentric contractions of the infraspinatus. In the limited relevant literature, convincing links between IA and performance or shoulder pathology have not been identified. IA in overhead sports is most likely of multi-factorial aetiology. Important questions about IA and its significance in overhead sports remain unanswered and more biomechanical and prospective studies are warranted to provide further insights into this athletic injury. 相似文献
16.
爆发力是快速力量为主导的体育项目中决定运动成绩的重要因素,爆发力的任何变化都有可能造成冠军或者名次的改变,因此如何在赛前准备活动中更大程度地提高运动员比赛时的爆发力成为近年来研究的重点。不断去追求和探索更加合理的、有效的激发运动员爆发力的方法和手段,成为运动员和教练员们所关注的内容。随着学界对于后激活增强效应(postactivation potentiation,PAP)的研究愈发深入,发现后激活增强效应有可能成为通过赛前准备活动提高运动员在比赛中爆发力的突破点,对PAP的功能及其在运动能力上应用的关注和研究与日俱增。许多研究人员在运动试验中,通过诱导出PAP提高了运动员的竞技表现,但因这些实验的变量选取纷繁复杂,研究多集中在PAP对运动能力即时性提升的效果,而PAP诱导效果的影响因素尚不明确。从生理机制、诱导条件与适用运动员特点3个方面进行梳理,分析研究PAP产生的生理机制,PAP进行诱导刺激所需的条件,以及适合通过PAP提高运动水平的运动员的特点,旨在为我国教练员和运动员在竞技训练实践中合理利用PAP提供有益参考。 相似文献
17.
“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
18.
运动心脏作为运动员所特有的＂高功能,高储备,大心脏＂一直被认为是运动员良好体能状态的重要保障,但在运动训练监控中我们发现一些运动员或多或少存在某些心脏结构改变和心律失常现象,往往影响运动员的系统训练和竞技水平的提高,常常困扰着运动员和教练员。运动医学研究也显示,在大运动量训练与反复大强度运动后运动心脏细胞与亚细胞的形态结构与功能代谢发生了某些失代偿性改变,引起运动性心肌微损伤,而且,右心房、右心室及内膜下心肌组织是运动心脏对大运动量训练与反复大强度运动的敏感区域,又称易损部位。尽管目前运动性心肌微损伤现象已为人所知,且运动性心律失常发生也与运动性心肌微损伤有关,但其病因、病理及发病机制尚不十分明了,运动员心肌微损伤与运动性心脏意外的发生很难早期诊断、预测和防治。针对优秀运动员潜在心脏隐患的调研也证实优秀运动员存在较高的心律失常风险,且专项训练年限长的运动员更为常见,一些运动员因此而退赛,甚至退役。运动性心律失常已经成为影响运动员体能、健康以及正常训练比赛的重要原因之一,制约了部分优秀运动员竞技水平和比赛成绩的提高。部分退役运动员留下了永久性的心律失常。本文主要针对运动性心律失常的常见类型以及病理变化与发生机制进行了综述与探讨,并对未来研究前景进行了展望,希望开展运动性心律失常电生和分子病理的研究,规避运动场上心血管意外的发生,保障运动员健康、延长运动寿命。 相似文献
19.
The BASES expert statement on emotion regulation in sport 总被引：1，自引：1，他引：0
Emotions experienced before and during sports competition have been found to influence sports performance. Emotion regulation is defined as the automatic or deliberate use of strategies to initiate, maintain, modify or display emotions (Gross & Thompson, 2007) and is proposed to occur when a discrepancy exists between current and desired emotions. Two distinct motivations to regulate emotion - hedonic and instrumental (in short, for pleasure or for purpose) - have been proposed (Tamir, 2009). The instrumental approach might provide a more fruitful area of investigation for sports researchers as some athletes hold beliefs that supposedly pleasant emotions such as happiness and calmness associate with poor performance and supposedly unpleasant emotions such as anxiety and anger associate with good performance (Hanin, 2010). Athletes are more likely to try to regulate an emotion if they believe that doing so will facilitate performance. Strategies that encourage re-appraisal of factors that trigger emotions are proposed to be preferable. In this British Association of Sport and Exercise Sciences (BASES) expert statement, a summary of the key theoretical issues are offered leading to evidence-based recommendations for practitioners and researchers. 相似文献
20.
运动性贫血与红细胞关系的研究进展 总被引：3，自引：0，他引：3
运动性贫血是竞技体育中从事高强度训练运动员中的一种常见症状，不仅影响运动员的训练水平和成绩，而且对身体健康造成危害。其发生机理有很多方面，其中运动引起红细胞的结构与功能的改变是运动性贫血发生的重要因素之一。近年来针对红细胞的研究发现红细胞膜的结构和红细胞的变形性两方面的异常与运动性贫血的发生有密切关系。以近年来的研究进展，从红细胞膜的结构和红细胞的变形性两方面进行综述，旨在探讨运动性贫血的发生机理，为科学防治提供理论依据。 相似文献