Dietary protein for athletes: from requirements to optimum adaptation

Opinion on the role of protein in promoting athletic performance is divided along the lines of how much aerobic-based versus resistance-based activity the athlete undertakes. Athletes seeking to gain muscle mass and strength are likely to consume higher amounts of dietary protein than their endurance-trained counterparts. The main belief behind the large quantities of dietary protein consumption in resistance-trained athletes is that it is needed to generate more muscle protein. Athletes may require protein for more than just alleviation of the risk for deficiency, inherent in the dietary guidelines, but also to aid in an elevated level of functioning and possibly adaptation to the exercise stimulus. It does appear, however, that there is a good rationale for recommending to athletes protein intakes that are higher than the RDA. Our consensus opinion is that leucine, and possibly the other branched-chain amino acids, occupy a position of prominence in stimulating muscle protein synthesis; that protein intakes in the range of 1.3-1.8 g · kg(-1) · day(-1) consumed as 3-4 isonitrogenous meals will maximize muscle protein synthesis. These recommendations may also be dependent on training status: experienced athletes would require less, while more protein should be consumed during periods of high frequency/intensity training. Elevated protein consumption, as high as 1.8-2.0 g · kg(-1) · day(-1) depending on the caloric deficit, may be advantageous in preventing lean mass losses during periods of energy restriction to promote fat loss.     

From evidence to policy: reflections on emerging themes in health-enhancing physical activity

Based on a detailed reading of the six preceding papers, in conjunction with a reflection on the socio-political forces shaping lifestyles in the UK at the turn of the millennium, we come to four interrelated conclusions. First, sport and exercise science needs to move beyond evidence-based practice to evidence-based policy. Second, sport and exercise science needs to make health-enhancing physical activity a political issue at both national and local level. Third, transport, not health policy, may be the key to promoting health-enhancing physical activity. And, fourth, young people deserve our special attention. In reaching these four interrelated conclusions, we attempt both to shape evidence based policy and future research agendas in exercise science. To achieve an international perspective, we also present a short case note from Australia.     

Nutritional needs of elite endurance athletes. Part II: Dietary protein and the potential role of caffeine and creatine

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).     

Protein and amino acids for athletes

The main determinants of an athlete's protein needs are their training regime and habitual nutrient intake. Most athletes ingest sufficient protein in their habitual diet. Additional protein will confer only a minimal, albeit arguably important, additional advantage. Given sufficient energy intake, lean body mass can be maintained within a wide range of protein intakes. Since there is limited evidence for harmful effects of a high protein intake and there is a metabolic rationale for the efficacy of an increase in protein, if muscle hypertrophy is the goal, a higher protein intake within the context of an athlete's overall dietary requirements may be beneficial. However, there are few convincing outcome data to indicate that the ingestion of a high amount of protein (2-3 g x kg(-1) BW x day(-1), where BW = body weight) is necessary. Current literature suggests that it may be too simplistic to rely on recommendations of a particular amount of protein per day. Acute studies suggest that for any given amount of protein, the metabolic response is dependent on other factors, including the timing of ingestion in relation to exercise and/or other nutrients, the composition of ingested amino acids and the type of protein.     

Self-compassion: a potential resource for young women athletes

Self-compassion has demonstrated many psychological benefits (Neff, 2009). In an effort to explore self-compassion as a potential resource for young women athletes, we explored relations among self-compassion, proneness to self-conscious emotions (i.e., shame, guilt-free shame, guilt, shame-free guilt, authentic pride, and hubristic pride), and potentially unhealthy self-evaluative thoughts and behaviors (i.e., social physique anxiety, obligatory exercise, objectified body consciousness, fear of failure, and fear of negative evaluation). Young women athletes (N = 151; Mage = 15.1 years) participated in this study. Self-compassion was negatively related to shame proneness, guilt-free shame proneness, social physique anxiety, objectified body consciousness, fear of failure, and fear of negative evaluation. In support of theoretical propositions, self-compassion explained variance beyond self-esteem on shame proneness, guilt-free shame proneness, shame-free guilt proneness, objectified body consciousness, fear of failure, and fear of negative evaluation. Results suggest that, in addition to self-esteem promotion, self-compassion development may be beneficial in cultivating positive sport experiences for young women.     

天津市部分大学生运动员和专业队运动员应对策略的比较研究

采用《中国运动员应对量表》,对天津市的68名大学生运动员和64名专业队运动员进行调查研究。结果表明,大学生运动员和专业队运动员在应对策略上分别以集中解决问题和集中处理情绪的直接应对为主,且在处理情绪维度上大学生运动员和专业队运动员存在显著性差异。大学生运动员的应对策略在集中处理情绪维度上存在性别差异,在遇到应激时,男大学生比女大学生运动员更加注重对情绪的处理。     

跆拳道运动员下肢爆发力测试与训练方法

采用文献资料、实验等研究方法,对跆拳道运动员下肢爆发力进行测试,探索提升其下肢爆发力的有效训练方法.结果表明:随着训练时间的增加,跆拳道运动员的下肢爆发力呈递增趋势;增强跆拳道运动员下肢爆发力可采用大力量训练法、快速小力量训练法、结合专项特点训练法等;选取具体训练方法时应充分考虑专项特点及运动员个体差异,因人而异,循序...     

世界女子体操优秀全能选手单项竞争力度及趋向分析

采用文献资料法、数理统计法和逻辑推理法,分析了当今世界女子体操优秀全能选手的单项竞争力度及趋向。结果表明：在2005年FIG“不封顶”新规则下,由2001年体操规则催生的单项奖牌扩大化趋势,在2005—2008年奥运周期内相对萎缩;全能选手的单项竞争力度将增大,但奖牌争夺将主要集中在高、平、自三个项目上,尤以高低杠争夺力度最大、其次是平衡木和自由体操;未来大赛具备“顶尖项目”的优秀全能型选手,将可获得较大的奖牌竞争空间。     

Paralympic sport: an emerging area for research and consultancy in sports biomechanics

The Paralympic Games are the pinnacle of sport for many athletes with a disability. The overall purpose of this paper is to highlight the role that the field of sports biomechanics specifically (and sports science in general) may play in improving performance in various summer Paralympic sports through research and consultancy. To achieve this broad aim, this review provides some history and background on the Summer Paralympic Games, discusses the eligibility and classification rules, describes the potential for the constraints-led approach of dynamical systems theory to inform practice and research in this area, and reviews selected studies examining the biomechanics of the primary forms of Paralympic locomotion. Some recommendations on how sports biomechanics can help facilitate improvements in Paralympic athletic performance through applied research and consultancy are provided, along with commentary on what may be some of the most important issues addressing Paralympic sport.     

影响我国高校学生运动员竞技能力的因素及解决对策

我国高校学生运动员的运动成绩与专业运动员相比存在着明显的差距,造成这一情景的原因是多方面的.诸如学生运动员的日常训练时间少、训练经费少、训练条件和训练设备差、营养补充不足、消除疲劳和控制伤病的措施少、比赛机会少、比赛奖金低、训练动机不强、高校体育教师的训练理论和实践水平不高、以及学生运动员自身的身体条件不够好等方面的原因.     

赛艇运动员测功仪速度素质的测试分析

通过研制的位移速度测试设备，对国家队备战2004奥运会双桨选手进行了测功仪拉桨速度的测试，揭示了测功仪训练的一些规律，为利用测功仪进行科学的训练提供依据。     

冰雪专项运动员素质教育的内容和途径

从思想政治素质、道德素质、科学化素质、心理素质、能力素质以及身体素质等几方面，论述冰雪专项运动员的综合素质的提高，为素质教育提供有效途径，从而为冰雪专项运动员取得更为优异的运动成绩提供保障。     

运动员心理唤醒量表的编制与初步分析

根据心理唤醒的概念模型，在对以往有关运动员心理唤醒测量工具的广泛研究和预备测试的基础上，编制出运动员心理唤醒量表(第1版)。采用“运动员心理唤醒量表”对240名运动员进行了测试。在对229份有效测验的项目分析基础上，剔除了第1版量表中的11个项目，形成了包括31个测验项目的运动员心理唤醒量表(第2版)。进一步的项目分析表明，运动员心理唤醒量表第2版各项目的区分度高，各分测验的内部一致性信度达到了心理测量学的基本要求。     

Branding athletes: Exploration and conceptualization of athlete brand image

In this study, the current issues of athlete brand management are discussed and the construct of athlete brand image is conceptualized. A conceptual model of athlete brand image (MABI) is developed incorporating three key dimensions: athletic performance, attractive appearance, and marketable lifestyle. These dimensions are defined by an athlete's on-field characteristics, attractive external appearance, and off-field marketable attributes. This study contributes to the sport branding literature by providing the first comprehensive conceptual framework of athlete brand image and offering managerial implications for building and managing the brand image of individual athletes.     

Eating disorders in athletes: Overview of prevalence,risk factors and recommendations for prevention and treatment

Abstract

The prevalence of disordered eating and eating disorders vary from 0–19% in male athletes and 6–45% in female athletes. The objective of this paper is to present an overview of eating disorders in adolescent and adult athletes including: (1) prevalence data; (2) suggested sport- and gender-specific risk factors and (3) importance of early detection, management and prevention of eating disorders. Additionally, this paper presents suggestions for future research which includes: (1) the need for knowledge regarding possible gender-specific risk factors and sport- and gender-specific prevention programmes for eating disorders in sports; (2) suggestions for long-term follow-up for female and male athletes with eating disorders and (3) exploration of a possible male athlete triad.     

对山东省高水平运动员输送状况和体系构建的研究

运用文献资料法、调查访问法、数理统计等,对我省高中学校与高校之间高水平运动员输送情况进行了调查分析.结果显示:我省高中学校与高校高水平运动员输送体系的形成和建设还不够完善,输送环节较为凌乱,输送渠道较为复杂,人际关系、社会因素干预较多等现象对运动员输送的整个过程不利.因此,建议教育行政部门应加强对运动员输送体系的监管力度,减少输送环节,保持"桥梁"的畅通,对我省高中学校运动队的发展壮大,高校高水平运动队的可持续性发展具有重要意义和作用.     

运动训练的基本体系及优秀运动员的实践途径(二)

运动训练科学化的根本出路在于认识与遵循规律。运动训练的基本规律,包括项目规律与训练规律。运动训练的基本体系框架中,运动训练理论主要是基于专项与个案训练理论,运动训练实践主要是基于目标与实战需要。运动训练的基本体系的基本内容主要有:项目规律与训练规律及其统一;一般训练与专项训练和群体训练与个案训练及其统一;选择和创造训练手段,包括一般与专项和群体与个体训练手段及其统一;发展和形成竞技能力,包括一般与专项竞技能力和群体与个体竞技能力及其统一。它们都是普遍性与特殊性的辩证关系。其中,个案训练理论,是训练规律的基本内容,是实践规律,在构成运动训练理论中个案训练理论与专项训练理论是同等程度的规律,个案训练理论还包括训练主体的意识与情感因素。优秀运动员的实践途径是专项训练与个案训练及其统一,选择与创造专项和个体训练手段及其统一,发展与形成专项与个体竞技能力及其统一。     

运动训练的基本体系及优秀运动员的实践途径(一)

运动训练科学化的根本出路在于认识与遵循规律.运动训练的基本规律,包括项目规律与训练规律.运动训练的基本体系框架中,运动训练理论主要是基于专项与个案训练理论,运动训练实践主要是基于目标与实战需要.运动训练基本体系的基本内容主要有:项目规律与训练规律及其统一;一般训练与专项训练和群体训练与个案训练及其统一;选择和创造训练手段,包括一般与专项和群体与个体训练手段及其统一;发展和形成竞技能力,包括一般与专项竞技能力和群体与个体竞技能力及其统一.它们都是普遍性与特殊性的辩证关系.其中,个案训练理论,是训练规律的基本内容,是实践规律,在构成运动训练理论中个案训练理论与专项训练理论是同等程度的规律,个案训练理论还包括训练主体的意识与情感因素.优秀运动员的实践途径是专项训练与个案训练及其统一,选择与创造专项和个体训练手段及其统一,发展与形成专项与个体竞技能力及其统一.     

大学生饮食行为与营养教育

采用简单随机抽样和分层抽样相结合的方法对师范类和综合性院校大一至大三男女大学生进行抽样调查。结果发现:我国大学生营养健康知识和饮食行为总体表现尚可,近半数学生具有荤素营养搭配的饮食观念及习惯,饮食较有规律,对营养素的态度及行为较正确。但存在着一些不健康的饮食行为,如主食摄入量过少、不重视早餐、挑食、膳食不平衡等,这与营养知识缺乏和健康知识的认知水平有关。建议在高校体育课程中增加营养教育内容,鼓励大学生多渠道获取营养知识和提高健康认知能力,改变不良生活行为,促进大学生的身心健康全面发展。