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1.
A low digit ratio (2D:4D) and low 2D:4D in the right compared with the left hand (right-left 2D:4D) are thought to be determined by high in utero concentrations of testosterone, and are related to "masculine" traits such as aggression and performance in sports like running and rugby. Low right-left 2D:4D is also related to sensitivity to testosterone as measured by the number of cytosine-adenine-guanine triplet repeats in exon 1 of the androgen receptor gene. Here we show that low right-left 2D:4D is associated with high maximal oxygen uptake (VO2(max)), high velocity at VO2(max), and high maximum lactate concentration in a sample of teenage boys. We suggest that low right-left 2D:4D is linked to performance in some sports because it is a proxy of high sensitivity to prenatal and maybe also circulating testosterone and high VO2(max). 相似文献
2.
The second to fourth digit ratio (2D:4D) is a sexually dimorphic trait with lower finger ratios considered more masculine. These digit ratios are believed to reflect the prenatal hormonal environment with higher exposure to androgens in utero leading to more masculine digit ratios. The 2D:4D ratio has been negatively correlated with many factors, including aggression, physical fitness, and athleticism. We compared 2D:4D finger ratios of (1) male and female varsity athletes (n = 99) versus male and female student non-athletes (n = 122), and (2) males (n = 104) versus females (n = 117). Our results confirmed that both male (mean ± s(x) : 0.97 ± 0.004) and female (0.98 ± 0.005) varsity athletes had significantly lower ratios than their non-varsity peers (males: 0.99 ± 0.004; females: 1.00 ± 0.006), and that male athletes had significantly lower 2D:4D ratios than female athletes. Overall, males had significantly lower 2D:4D ratios than females (0.98 ± 0.003 vs. 0.99 ± 0.004). A smaller 2D:4D ratio appears to be consistent with participation in varsity sports among both males and females. 相似文献
3.
Abstract The relative length of the second and fourth digits (2D:4D) is a putative marker for prenatal testosterone. Low 2D:4D has been reported to correlate with high performance in sport in general. Here, for the first time, we examine the relationship between 2D:4D and performance in elite rugby players. The 44 players (28 forwards, 16 backs) were drawn from the Ospreys Rugby Union Club and 44 age-matched controls. The measures of performance comprised age-adjusted number of international performances (caps) for Wales, a comparison of coaches' first-choice League team with others, and the number of tries scored by backs in club matches. Compared with controls, players were larger and had lower 2D:4D for the right and left hand. With regard to number of caps, players with low 2D:4D in their right hand and low right 2D:4D compared with their left (right ? left 2D:4D difference) had high numbers of caps. First-choice players did not differ significantly from second-choice players in their 2D:4D but they did have a lower right ? left 2D:4D difference than second-choice players. Low right 2D:4D and low right ? left 2D:4D difference were significantly linked with large numbers of tries. We conclude that low right 2D:4D and low right ? left 2D:4D difference are predictors of high rugby performance. 相似文献
4.
The relative length of the second and fourth digits (2D:4D) is a putative marker for prenatal testosterone. Low 2D:4D has been reported to correlate with high performance in sport in general. Here, for the first time, we examine the relationship between 2D:4D and performance in elite rugby players. The 44 players (28 forwards, 16 backs) were drawn from the Ospreys Rugby Union Club and 44 age-matched controls. The measures of performance comprised age-adjusted number of international performances (caps) for Wales, a comparison of coaches' first-choice League team with others, and the number of tries scored by backs in club matches. Compared with controls, players were larger and had lower 2D:4D for the right and left hand. With regard to number of caps, players with low 2D:4D in their right hand and low right 2D:4D compared with their left (right?-?left 2D:4D difference) had high numbers of caps. First-choice players did not differ significantly from second-choice players in their 2D:4D but they did have a lower right?-?left 2D:4D difference than second-choice players. Low right 2D:4D and low right?-?left 2D:4D difference were significantly linked with large numbers of tries. We conclude that low right 2D:4D and low right?-?left 2D:4D difference are predictors of high rugby performance. 相似文献
5.
Abstract In this study the relationship between the digit ratio (2D:4D) and artistic gymnastics performance and competition level was investigated in a sample of Caucasian world-class female gymnasts (n = 145). The sample was divided into three competition events (compulsories, free work, final score). Within each event three performance groups (lowest, middle, and highest) were based on the competition scores gathered at the World Championships at Rotterdam, the Netherlands, in 1987. Lengths of the digits were measured on X-rays of the left hand. Several anthropometric dimensions were measured and from those measurements an androgyny index (Bayer & Bayley) and somatotype components (endomorphy, mesomorphy, ectomorphy) were calculated. Although significant differences in some anthropometric characteristics between the performance level groups within each competition event were observed, no significant differences in the 2D:4D ratios were found between the performance level groups, varying from 0.918 ± 0.020 to 0.924 ± 0.020. Also, no significant correlations were observed between the 2D:4D ratio and anthropometric, androgyny, and somatotype characteristics, r varying from r = –0.11 to r = +0.12. It can be concluded that in this sample the 2D:4D digit ratio, unlike other anthropometric characteristics, is not a discriminating factor for the performance in artistic gymnastics performance on a world-class level. 相似文献
6.
Liam Kilduff Christian J. Cook Mark Bennett Blair Crewther Richard Michael Bracken John Manning 《Journal of sports sciences》2013,31(6):677-683
Abstract There is evidence that the digit ratio (2D:4D) is a negative correlate of prenatal levels of testosterone, but there is no association between 2D:4D and the circulating levels of both total and free testosterone. Sports provide a physical challenge and participants often show increased levels of free testosterone immediately preceding and during competition. We tested this hypothesis of a link between 2D:4D and testosterone under challenge in 79 professional rugby players using the following procedures; (i) 25 players were physically challenged using a repeated sprint agility test, and saliva samples were assayed for testosterone immediately preceding the repeated sprint agility test (time 1) and 5 minutes (time 2) and 20 minutes after completion of the repeated sprint ability (time 3); (ii) 54 players were also tested for salivary testosterone in an unchallenged condition. We found that right-left 2D:4D was significantly and negatively related to testosterone concentrations at times 1, 2 and 3 following the repeated sprint agility test (P < 0.05) and there was no association between the 2D:4D and basal testosterone levels in the unchallenged group. We suggest that low right–left 2D:4D is a predictive marker of free testosterone responsiveness when trained men are physically challenged, and that this association is programmed by the action of prenatal testosterone. 相似文献
7.
For fencing, speed of the lunge is considered critical to success. The aim of this study is to investigate determinants of lunge speed based on biomechanics. Ground reaction force (GRF) and three-dimensional kinematic data were collected from 7 elite fencers and 12 intermediate-level fencers performing maximum-effort lunges. The results showed that elite fencers acquired a higher horizontal peak velocity of the centre of gravity (HPV) and concomitantly a higher horizontal peak GRF exerted by rear leg (PGRF) than intermediate-level fencers (P?P?P?P?≤?.05). Our findings suggest that training aimed at enhancing strength and power of rear knee extensors is important for fencers to improve speed of the lunge. Also, increasing the extension of rear knee during the lunge, at the same time decreasing the flexion of the forward knee before extension are positive for lunge performance. 相似文献
8.
要保持我国跳水项目在世界上的优势,必须发展转体动作的难度。为使更多运动员尤其是青少年能够成功顺利地掌握跳台反身转体5337D（即反身翻腾一周半转体三周半）动作,在梳理以往教学方法实践的基础上,提出了保留弹网保护带及陆上辅助措施,避开陆上跳板,水上一米板,三米板的诱导动作,转换成三米台、七米台的诱导动作等新的构思,使转体动作的学习过程简单化,提高学习转体过程的成功率。 相似文献
9.
Brian E. Udermann John M. Mayer Steven R. Murray 《Research quarterly for exercise and sport》2013,84(4):434-437
Abstract One hundred and eighteen national collegiate fencers engaged in the first round competition in the 28th annual NCAA Fencing Championships held at the University of Illinois, Chicago Circle Campus. After the first day of competition, the field size was reduced to 72 fencers or 24 fencers per weapon. Through the use of a unique scoring device, response times and accuracy measurements were recorded for each fencer. The fencers then engaged in their respective round robin tournament according to class of weapon; epee, sabre, or foil. Two criterion measures of fencing success were then correlated with response times and accuracies. Correlation coefficients for sabre fencemen were slightly better than 0. Criterion measures for epee fencers showed a low relationship with response time and accuracies while those of foil showed a slight to fair relationship. 相似文献
10.
AbstractInterest in Vitamin D has risen considerably recently with many athletes now advised to take daily vitamin D supplements. The reason for this interest is partly not only attributed to the resurgence of the Vitamin D-deficient disease rickets but also due to the discovery of a Vitamin D receptor in many tissues suggesting a more global role for Vitamin D than previously considered. Unlike the other vitamins that are obtained through the diet, Vitamin D is unique since endogenous synthesis following ultraviolet B (UVB) exposure is the predominant route of entry into systemic circulation. Moreover, Vitamin D could be better classed as a seco-steroid, given that its structure is similar to that of a steroid, and its production is derived from a cholesterol precursor (7-dehydrocholesteol) in the skin. The classification of Vitamin D status is currently subject to considerable debate with many authors opposing governing body recommendations. Regardless of the suggested optimal concentration, there is now growing evidence to suggest that many athletes are in fact Vitamin D deficient, especially in the winter months largely as a consequence of inadequate sun exposure, combined with poor dietary practices, although the consequences of such deficiencies are still unclear in athletic populations. Impaired muscle function and reduced regenerative capacity, impaired immune function, poor bone health and even impaired cardiovascular function have all been associated with low Vitamin D in athletes, however, to date, the majority of studies on Vitamin D have described associations and much more research is now needed examining causation. 相似文献
11.
目的:通过对重剑运动员赛前训练血乳酸的测试,评定不同训练手段对提高专项对抗能力的作用和效果,为教练员进行针对性训练、科学安排训练提供依据。方法:以安徽省击剑队重剑组8名运动员为研究对象,应用血乳酸指标对不同训练手段后的即刻、5min后的血乳酸值进行监测,并与全国比赛的有关测试结果进行比较分析。结果:1)个别课、条件对练、站桩练习、团体实战后即刻BLA与全国比赛后有非常显著差异(P<0.01);2)个人实战后即刻BLA与全国比赛后有显著差异(P<0.05)。结论:1)重剑运动员在发展ATP-CP系统供能能力基础上,应当重视糖酵解供能能力训练,尤其是一定量的最高乳酸训练;2)不同的训练手段重剑运动员所表现出的BLA结果各不相同;同一种训练手段,不同的运动员所表现出的BLA也有差异;3)个别课、条件对练、站桩练习、团体实战四种训练手段的运动强度较低,均不是提高重剑运动员赛前专项对抗能力的理想训练手段;4)个人实战训练手段中,在对手安排和比赛气氛的营造上,应使之更接近全国比赛,以满足比赛时对大强度负荷的要求。 相似文献
12.
目的:探讨现代五项和击剑项目运动员非蛋白能量消耗和能量摄入的特点。方法 选取上海现代五项、击剑优秀运动员,共17人。第1天和第3天清晨空腹测定静息能量代谢 （resting energy expenditure,REE）,并进行身体形态检查（身高、体重、体成分）。连续3天填写饮食记录表（dietary record,DR）,采用食物称重法计算膳食能量摄入（energy intake,EI）。结果：（1）上海现代五项和击剑项目运动员每天的饮食摄入低于实际能量消耗。（2）现代五项和击剑运动员的非蛋白能量物质摄入量均低于推荐值。（3）在静息状态下,现代五项和击剑运动员的静息能量代谢无明显差异（P=0.935）,糖脂供能比均接近1.1：1。（4）现代五项和击剑运动员的日均能量摄入无明显差异（P=0.929）,但与推荐糖脂比例相比,现代五项的碳水化合物摄入不足,而击剑运动员的碳水化合物和脂肪摄入比例相对合理。结论：（1）上海现代五项和击剑项目运动员每日的非蛋白能量物质碳水化合物摄入明显不足,需要在饮食中进一步加强补充。（2）现代五项运动员的碳水化合物与脂肪摄入比例需要进一步优化。 相似文献
13.
运用录像观察法、数理统计法等对参加第42届世锦赛男子单杠决赛的8名运动员成套动作的"D"分及构成情况、动作的编排情况进行了对比分析。研究表明:新周期男子单杠的"D"分呈不断增长的趋势,在本周期内的余下体操大赛中,单杠决赛的"D"分均值将保持在7分以上;成套难度动作价值对单杠"D"分的增长贡献较小,而成套连接价值的增加对其贡献最大。新周期单杠项目的编排亦具有如下特征:1)单杠项目的杠上动作难度保持在D组水平,不断发展杠上动作与飞行动作间的连接成为趋势;2)单杠项目的飞行动作中,D、E组难度价值的动作将迅速发展,而且在成套单杠动作编排中,飞行动作的出现将伴随连接价值的产生,其数量也将向4个发展;3)单杠项目进入了高难连接的发展阶段,并在连接类型及动作上呈多样化发展趋势;4)单杠下法动作依旧以直体后空翻2周720°旋下为主流,对下法动作的编排将以稳定性为原则。 相似文献
14.
《European Journal of Sport Science》2013,13(4):364-371
Abstract The aim of the present work is to examine the differences between two groups of fencers with different levels of competition, elite and medium level. The timing parameters of the response reaction have been compared together with the kinetic variables which determine the sequence of segmented participation used during the lunge with a change in target during movement. A total of 30 male sword fencers participated, 13 elite and 17 medium level. Two force platforms recorded the horizontal component of the force and the start of the movement. One system filmed the movement in 3D, recording the spatial positions of 11 markers, while another system projected a mobile target over a screen. For synchronisation, an electronic signal enabled all the systems to be started simultaneously. Among the timing parameters of the reaction response, the choice reaction time (CRT) to the target change during the lunge was measured. The results revealed differences between the groups regarding the flight time, horizontal velocity at the end of the acceleration phase, and the length of the lunge, these being higher for the elite group, as well as other variables related to the temporal sequence of movement. No significant differences have been found in the simple reaction time or in CRT. According to the literature, the CRT appears to improve with sports practice, although this factor did not differentiate the elite from medium-level fencers. The coordination of fencing movements, that is, the right technique, constitutes a factor that differentiates elite fencers from medium-level ones. 相似文献
15.
运动和胰岛素是诱导骨骼肌葡萄糖转运的两种重要生理因素，两者均能通过不同的信号转导通路诱导GLUT4从细胞内转位到细胞膜表面，从而调控骨骼肌的葡萄糖转运。研究表明，TBC1家族结构域家族成员蛋白激酶B蛋白底物160KDa（AS160/TBC1D4）和TBC1D1这两种同源蛋白均可在运动或胰岛素诱导下发生磷酸化，两者可能是运动和胰岛素调控骨骼肌葡萄糖转运信号通路的关键汇聚点。综述AS160与TBC1D1在胰岛素诱导骨骼肌葡萄糖转运中的不同作用以及运动/骨骼肌收缩对其的影响及其机制，以期深入了解运动如何改善胰岛素敏感性、为更科学的运动处方及其他干预措施的研发提供有价值的理论支持。 相似文献
16.
Harry A. King 《Research quarterly for exercise and sport》2013,84(3):404-412
Computer simulation techniques were used to study the accuracy with which true rankings of table tennis players could be estimated from round robin tournaments based on matches of different length. Tournaments based on best-of-three-games, 21-points-to-win, and 11-points-to-win matches were studied. The simulation design also allowed study of the effect of both the number of players and the homogeneity of their ability on the efficacy of the three types of tournaments. Accuracy of the rankings produced by different types of tournaments was ascertained by computing Spearman's Rho rank correlations between the known, true ranking (known from the statistical model on which the simulated model was based) and empirical rankings in repeated tournaments. Results demonstrated that for groups of players of mixed ability, tournaments based on matches of shortened length were highly effective in estimating the true ranking, Spearman's Rho coefficients being generally well above .90. Tournaments based on longer matches exhibited only a small increase in accuracy of estimation of the true rankings. The difference between mean Spearman's Rho coefficients for tournaments based on best-of 3-games and 21-point matches approximated .02; between coefficients for tournaments based on 21-point matches and 11-point matches this difference approximated .03. 相似文献
17.
Clemens Müller Thorsten Sterzing Justin Lange Thomas L. Milani 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):193-205
The purpose of this study was to evaluate the traction characteristics of four different stud configurations on Fédération Internationale de Football Association (FIFA) 2-Star, third-generation artificial soccer turf. The investigated stud configurations were hard ground design, firm ground design, soft ground design, and an experimental prototype. The concept of this study combines performance, perception, biomechanical, and mechanical testing procedures. Twenty-five soccer players took part in the different testing procedures. Variables of this study were: running times, subjective rankings/ratings, ground reaction forces, and mechanical traction properties. Statistical discrimination between the four stud configurations was shown for performance, perception, and biomechanical testing (p < 0.05). Unsuited stud configurations for playing on artificial turf are characterized by less plain distributed and pronounced studs. 相似文献
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19.
目的:通过研究运动及多巴胺II型受体(dopamine type II receptor,D2R)激动剂干预对PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应的影响,揭示运动在改善PD小鼠基底神经节信息输出中的作用及机制。方法:选用4周龄雄性D2-Cre小鼠,右侧纹状体注射兴奋性光敏感蛋白病毒(rAAV-Ef1α-DIO-ChR2-EYFP-WPRE-pA),通过光遗传技术精准操控D2MSN。小鼠随机分为对照组(D2-Cre)和模型组,纹状体分别注射生理盐水和神经毒素6-羟基多巴胺(6-Hydroxydopamine hydrobromide,6-OHDA),经鉴定符合PD标准的模型组小鼠再分为PD组(PDD2-Cre)和PD运动组(PD+Ex D2-Cre)。采用4周匀速跑台运动(18 m/min,40 min/天,连续5天/周)和D2R激动剂分别对各组小鼠进行干预。实验结束后,制备离体脑片,利用全细胞膜片钳结合光遗传技术检测各组小鼠纹状体D2MSN-D1MSN侧抑制效应及黑质网状部的信息输出,并验证侧抑制效应的变化是否由D2R介导。结果:光刺激D2-MSN后,D1-MSN动作电位发放个数PDD2-Cre组显著低于D2-Cre组(P<0.05);PD+ExD2-Cre组显著高于PDD2-Cre组,但仍低于D2-Cre组(P<0.05)。光刺激D2-MSN诱发D1-MSN抑制性突触后电流(Optogenetic stimulation evoked inhibitory postsynaptic currents,oIPSC)的幅值与基线比值,PDD2-Cre组显著高于D2-Cre组(P<0.05),PD+ExD2-Cre组显著低于PDD2-Cre组,但高于D2-Cre组(P<0.05);光刺激D2-MSN诱发黑质网状部(SNr)抑制性突触后场电位(field inhibitory post synaptic potential,fIPSP)最大幅值,PDD2-Cre组显著低于D2-Cre组(P<0.05),PD+ExD2-Cre组显著高于PDD2-Cre组,但低于D2-Cre组(P<0.05)。结论:PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应异常,并影响了SNr的信息输出,这可能是导致PD基底神经节功能紊乱的重要原因之一。4周运动干预通过改善PD模型小鼠纹状体D2MSN-D1MSN侧抑制效应,调节了SNr的信息输出。D2R在运动改善PD小鼠纹状体D2MSN-D1MSN侧抑制效应和调节基底神经节信息输出中起重要作用。 相似文献