第34届世界体操锦标赛中国男子体操队实力分析

采用调查访问法、录像统计法和资料研究法对第 34届世界体操锦标赛男子团体前 6名、全能前 36名、单项前 8名运动员的比赛成绩、动作难度及完成情况进行了统计并与中国队进行了对比与研究。结果表明 :中国队的团体实力在短期内仍能够保持领先的地位 ,俄罗斯队的实力不容忽视。中国队不乏全能型运动员 ,但他们在个别项目上均存在弱项。中国队在单项上有实力夺取更多的金牌 ,但在成套动作的编排、稳定性和心理素质等方面还有待提高。     

论南拳运动员的速度力量训练

南拳的核心是劲力,没有速度就不会有劲力的体现,而要提高速度,增强速度力量是关键措施之一,文章从训练实践角度,并结合理论,较全面地分析了南拳运动员速度力量训练的重要性,并对如何提高南拳运动员的速度力量提出几点建议.     

我国与奥运强国竞技体育实力的比较研究

运用文献资料、数理统计等方法,对我国与奥运强国竞技体育实力的比较研究表明,中国与第一集团的竞技实力尚存在着差距。主要表现为:获奖面、三大球和两大基础项目及男子竞技项目成绩等方面的差距;中国要与美、俄并称世界竞技体育第一集团,除保持现有优势项目外,需寻找新的金牌增长点;提高金牌数量较多的两大基础项目、水上项目、男子运动员的竞技实力是实现我国竞技体育可持续发展的重要途径。     

浅谈太极拳推手力学原理

文章阐述了太极推手过程中劲力的作用,并从运动力学的角度和应用的角度探究太极拳推手过程的原理,剖析＂开合劲＂＂,螺旋劲＂＂,串劲＂,＂抖劲＂4种劲力在推手中的机理。     

亚洲女子田径运动员竞技实力分析

据现代竞技运动发展特征,以亚洲女子田径运动员在历届世界大赛成绩,创造世界纪录以及当前世界和亚洲纪录为切入点,运用文献资料法,数理统计法、逻辑分析法等,尝试量化分析亚洲女子田径运动发展的轨迹,揭示其规律和特征,为确立今后发展方向并提高运动水平提供研究依据。研究表明：在竞技体育发展的新技术和大负荷阶段除个别项目在某个阶段具有一定优势外,整体运动水平落后于世界;科学化训练阶段获奖项目和国家增多,优势在周期耐力性和投掷类项目。百余年间有3个国家和1个地区运动员在14个奥运项目上创造或平过世界记录;当前亚洲地区女子田径运动开展不均衡。     

江苏高职院校女子篮球运动员力量素质训练研究

根据篮球专项力量素质在篮球运动中的重要性,从实际训练的角度出发论述江苏省高职院校女子篮球运动员专项力量素质训练的有关问题。     

Test–retest reliability of a battery of field-based health-related fitness measures for adolescents

Abstract

The main aim of this study was to determine the test–retest reliability of existing tests of health-related fitness. Participants (mean age 14.8 years, s = 0.4) were 42 boys and 26 girls who completed the study assessments on two occasions separated by one week. The following tests were conducted: bioelectrical impedance analysis (BIA) to calculate percent body fat, leg dynamometer, 90° push-up, 7-stage sit-up, and wall squat tests. Intra-class correlation (ICC), paired samples t-tests, and typical error expressed as a coefficient of variation were calculated. The mean percent body fat intra-class correlation coefficient was similar for boys (ICC = 0.95) and girls (ICC = 0.93), but the mean coefficient of variation was considerably higher for boys than girls (22.2% vs. 12.2%). The boys' coefficients of variation for the tests of muscular fitness ranged from 9.0% for the leg dynamometer test to 26.5% for the timed wall squat test. The girls' coefficients of variation ranged from 17.1% for the sit-up test to 21.4% for the push-up test. Although the BIA machine produced reliable estimates of percent body fat, the tests of muscular fitness resulted in high systematic error, suggesting that these measures may require an extensive familiarization phase before the results can be considered reliable.     

Alterations in Strength and Maximal Oxygen Uptake Consequent to Nautilus Circuit Weight Training

Abstract

The purpose of this study was to determine the effects of a Nautilus circuit weight training program on muscular strength and maximal oxygen uptake ([Vdot]O ₂ max) by comparing these effects to those produced by adhering to either a free weight (FW) strength training program or a running (R) program. Male college students who voluntarily enrolled in either a FW training class (n = 11), a Nautilus (N) circuit weight training class (n= 12), or a R conditioning class (n= 13) were subjects for this investigation. All groups participated in their respective programs 3 days per week for 10 weeks. Strength was assessed using a Cybex II isokinetic dynamometer set at an angular velocity of 60° · s ^?1 and a damping of 2. The FW group served as the control group for the assessment of [Vdot]O ₂ max changes, while the R group served as controls for the assessment of strength differences. ANCOVA revealed that the N and R groups experienced significant (p < .01) increases in [Vdot]O ₂ max expressed in L · min ^?1 (10.9 and 11.4%), ml · kg ^?1 · min ^?1 (10.8 and 11.7%), and ml · kgLBW ^?1 · min ^?1 (7.1 and 7.5%) when compared to the FW group. There were no significant differences between the N and R groups. There were no significant differences among groups in final peak torque values (after covariance), and torque at the beginning and end of the range of motion for the knee extensors, knee flexors, elbow extensors, and elbow flexors. In general, isokinetic strength values elicited by the N group compared favorably to those generated by the FW group. It was concluded that for a training period of short duration, Nautilus circuit weight training appears to be an equally effective alternative to standard free weight (strength) and aerobic (endurance) training programs for untrained individuals.     

Electromyography activities for shoulder muscles over various movements on different torque changes

Abstract

The aim of the present study was to investigate the patterns of shoulder muscle activation and joint torques during maximal effort eccentric contractions with shoulder extension, abduction, and diagonal movements on the isokinetic device. Participants in this investigation were nine men and four women with no history of shoulder injury or disorders. They all participated in overhead sports at least three days a week, and volunteered to participate in this study for shoulder isokinetic muscle strength testing. They performed eccentric muscle action with shoulder flexion, abduction, and diagonal movements at velocities of 60 rad·s^?1 and 180 rad· s^?1, which was followed alternately by passive shoulder flexion, abduction and diagonal movement at a velocity of 30 rad· s^?1, and total range of motion was standardised to 90°. Electromyography (EMG) and torque values were calculated to every 10°, except for the start and end 5° during each task. During each test, the isokinetic force output and muscle activation were synchronised. EMG data were normalised by percentage of maximum voluntary isometric contraction (%MVIC). EMG signals were recorded by surface EMG from the anterior deltoid (AD), middle deltoid (MD), posterior deltoid (PD), upper trapezius (UT), middle trapezius (MT), and biceps brachii (BB) muscles during this test. All of the muscle patterns were significantly decreased at the last compared with the initial part during eccentric shoulder flexion movement, except for the BB muscle (P < 0.05). AD and BB muscles played a similar role when peak torque was generated under load during eccentric muscle action with varying shoulder movements. PD and UT muscle activities were significantly lower than the other muscle activities during eccentric contraction with shoulder flexion and abduction movements, and the PD and UT muscles played a significant role in conjunction with MD and MT muscles in varying degrees during eccentric contraction with shoulder diagonal movements at 180 rad·s^?1 (P < 0.05). Our study demonstrated that MT muscle activity was greatly influenced when torque values showed a peak moment under load during maximum effort, eccentric contraction with shoulder abduction and diagonal movements. However, the MD, PD, UT, and MT muscle activities had no great influence when peak torque was generated under load during eccentric muscle action with shoulder diagonal movement at high velocity. The present study suggested that varying eccentric muscle activity patterns may be needed to investigate proper training and functional contributions of upper extremity muscles to stabilisation of the shoulder joint when peak torque was generated under load.     

Acute caffeine ingestion enhances strength performance and reduces perceived exertion and muscle pain perception during resistance exercise

Abstract

The efficacy of caffeine ingestion in enhancing aerobic performance is well established. However, despite suggestions that caffeine may enhance resistance exercise performance, research is equivocal on the effect of acute caffeine ingestion on resistance exercise performance. It has also been suggested that dampened perception of perceived exertion and pain perception might be an explanation for any possible enhancement of resistance exercise performance due to caffeine ingestion. Therefore, the aim of this study was to examine the acute effect of caffeine ingestion on repetitions to failure, rating of perceived exertion (RPE) and muscle pain perception during resistance exercise to failure. Eleven resistance trained individuals (9 males, 2 females, mean age±SD=26.4±6.4 years), took part in this double-blind, randomised cross-over experimental study whereby they ingested a caffeinated (5 mg kg^?1) or placebo solution 60 minutes before completing a bout of resistance exercise. Experimental conditions were separated by at least 48 hours. Resistance exercise sessions consisted of bench press, deadlift, prone row and back squat exercise to failure at an intensity of 60% 1 repetition maximum. Results indicated that participants completed significantly greater repetitions to failure, irrespective of exercise, in the presence of caffeine (p=0.0001). Mean±S.D of repetitions to failure was 19.6±3.7 and 18.5±4.1 in caffeine and placebo conditions, respectively. There were no differences in peak heart rate or peak blood lactate values across conditions (both p >0.05). RPE was significantly lower in the caffeine compared to the placebo condition (p=0.03) and was significantly higher during lower body exercises compared to upper body exercises irrespective of substance ingested (p=0.0001). For muscle pain perception, a significant condition by exercise interaction (p=0.027) revealed that muscle pain perception was lower in the caffeine condition, irrespective of exercise. With caffeine, pain perception was significantly higher in the deadlift and back squat compared to the bench press. However, with placebo, pain perception was significantly higher for the deadlift and back squat compared to the prone row only. Therefore, acute caffeine ingestion not only enhances resistance exercise performance to failure but also reduces perception of exertion and muscle pain.