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1.
Abstract

A horizontal adductive arm swing executed at maximal speed, and timed at intervals of 15°, 53°, 90°, and 105°, was studied under two experimental conditions. Although the movement completed was the same in both conditions, the fundamental difference between the “normal” and “pre-tensed” arm movements was that in the latter condition the subject built up his arm strength maximally just prior to initiating the movement. Twenty trials under each condition was performed by 60 college men. All reliability coefficients were found to be high, i.e., over .89. In contradiction to expectations, the relationship between premovement strength and speed of movement at the first station (r = -.208) was lower than anticipated. However, the low correlations found between strength and speed of movement are in general agreement with the results of earlier investigators which have substantiated the predominance of neuromotor specificity.  相似文献   

2.
Abstract

The purpose of this study was twofold: to determine which exercise program was most effective in producing a static strength gain and to determine the relationship between static strength and speed of movement. Seventy-two eighth grade girls were divided into two experimental groups one using an isometric exercise program, the other using an isotonic program. A control group played lead-up games during the experimental period. Strength and speed of the arm and shoulder girdle were both measured by three tests. Prior to training, correlations indicated a rather high relationship between static strength, and speed of a dominant arm movement. Following training there was little relationship between static strength, and speed of a specific arm movement. The results of the training program indicated an increase in mean performance in all three groups with the isotonic group being superior.  相似文献   

3.
Abstract

The experiment was designed to compare the effects of isometric-isotonic (A), dynamic-overload (B), and free swing (C) exercise programs on the speed and strength of a lateral arm movement The 26 college men in each group—three experimental and one control—were given pre- and post-training speed and strength trials. Each experimental group performed its assigned exercise twice a week during the 10-week training period. Reliability coefficients for both strength and speed of movement measurements were found to be high. Following training there were significant speed increases in both the isometric-isotonic and dynamic-overload groups (t=10.06 and 8.10; however, the difference in speed gain between conditions was nonsignificant (F=.10). Also, strength increases in both of these groups were significant (t=8.81 and 3.08), with that of the isometric-isotonic group significantly greater than the dynamic-overload group (F=5.11). No significant speed or strength gains were registered by either the free swing or control group.  相似文献   

4.
Abstract

Speed of movement in a lateral adductive arm swing was timed at seven equidistant points on an arc of 120 degrees. Static strength and effective arm mass were measured in the movement position. Data obtained on 36 men and 36 women were subjected to a centroid factor analysis. The structure for both sexes consisted of a single common factor for arm speed and a substantial item-specific factor for the first 17 cm. of movement, suggesting that the velocity curve probably consisted of two components. The correlations between the strength/mass ratios and speeds of movement were almost zero, except in the middle phase of the action, where the relationship was .29 for men and .27 for women (.36 and .34 when corrected for attenuation). These very low correlations supported the hypothesis of neuromotor specificity. Circumferential speed for women was 17 percent slower than for men, partly because their arms were shorter. In angular speed, the sex difference was only 5 percent.  相似文献   

5.
运用三维测力台系统和红外光点运动分析系统同步测试的方法,定量测试分析运动员杠铃负重量半蹲练习过程中,人体对地面的跨伸力、对杠铃的作功率和杠铃在人体作用下运动的加速度、末速度、动量等参数指标与负荷重量的相互关系;及各参数指标的最大值与弹跳力的相关关系。为继不同训练水平的运动员发展弹跳力的力量素质训练内容的定向化、负荷重量的定量化提供了科学的理论依据。  相似文献   

6.
Abstract

This study investigated the relationship between strength and speed of forearm flexion and compared the effect of three methods of training on speed of forearm flexion movement. Ninety-one university freshmen were tested for maximum static strength, forearm mass, and speed of forearm flexion. They were assigned to four groups: control, speed of movement, isometric, and isotonic. After an 8-week experimental program, subjects were tested again for strength, mass, and speed of forearm flexion movement. Low positive relationships, significant at the .05 level, between static strength and speed of forearm flexion were found in this study. When static strength was related to the mass which was moved during movement, correlations between strength/mass and speed were not significant. The results of both correlational computations and covariance analysis indicated that increasing the strength of the muscles which move a limb does not result in a corresponding increase in the speed with which the limb can be moved.  相似文献   

7.
The arm swing in hockey skating can have a positive effect on the forces produced by each skate, and the resulting velocity from each push off. The main purpose of this study was to measure the differences in ground reaction forces (GRFs) produced from an anteroposterior versus a mediolateral style hockey skating arm swing. Twenty-four elite-level female hockey players performed each technique while standing on a ground-mounted force platform, and all trials were filmed using two video cameras. Force data was assessed for peak scaled GRFs in the frontal and sagittal planes, and resultant GRF magnitude and direction. Upper limb kinematics were assessed from the video using Dartfish video analysis software, confirming that the subjects successfully performed two distinct arm swing techniques. The mediolateral arm swing used a mean of 18.38° of glenohumeral flexion/extension and 183.68° of glenohumeral abduction/adduction while the anteroposterior technique used 214.17° and 28.97° respectively. The results of this study confirmed that the mediolateral arm swing produced 37% greater frontal plane and 33% less sagittal plane GRFs than the anteroposterior arm swing. The magnitudes of the resultant GRFs were not significantly different between the two techniques; however, the mediolateral technique produced a resultant GRF with a significantly larger angle from the direction of travel (44.44°) as compared to the anteroposterior technique (31.60°). The results of this study suggest that the direction of GRFs produced by the mediolateral arm swing more closely mimic the direction of lower limb propulsion during the skating stride.  相似文献   

8.
Abstract

Forearm flexion strength of 65 college men was measured at two distances from the elbow at each of three angles of the forearm. The speed of forearm flexion movement was measured through an arc of 85°. Ebel intraclass reliabilities for strength and speed were high, i.e., .95 to .99. The extremely low correlations between limb strength and speed of movement, which ranged from —.06 to .14, are in agreement with the majority of the low correlations reported in earlier studies. The findings of this study support the theory of specificity in that individual differences in the speed of a limb involving a single joint are predominantly independent of strength measures associated with that limb and joint.  相似文献   

9.
Abstract

Ages, heights, weights, and 24 static (cable tensiometer) strength test scores were obtained from 81 college men enrolled in service course classes at the University of Oregon during the 1963–64 academic year. Of the 276 intercorrelations between strength scores, 215 were significant (p > .01; r ≥ .285). In general, when age, height, and weight were held constant, the intercorrelations between the strength scores from the different segments of the body were not greatly changed from those of the zero-order correlations between the same strength scores. Five functional clusters or groupings of strength were isolated and identified by means of the application of cluster analysis to the intercorrelations between the strength tests and by an analysis of muscle actions involved in the performance of each of the strength tests. The findings in this study disclosed five clusters or groupings of strength which were specific to shoulder, trunk, neck, wrist, and hip joints. They could also be described as arm and forearm strength, trunk strength, neck strength, hand strength, and thigh and leg strength.  相似文献   

10.
体育舞蹈的运动技术特征及其专项力量训练   总被引：2，自引：0，他引：2       下载免费PDF全文
分析体育舞蹈各舞种动作技术形成的内在机理,认为其运动技术特征主要表现在5个方面:一是保持正确身体姿态的控制技术;二是身体重心快速而有节奏的弹动技术;三是身体重心以抛物状和螺旋状运动技术;四是髋部与腰腹部强劲扭摆技术;五是胸、背、肩部和手臂的律动技术。针对体育舞蹈项目的运动技术特征,归纳总结出发展体育舞蹈选手静力性控制力量、速度力量、力量耐力和相对力量的训练方法和手段,提出了训练中应遵循的几个重要原则。  相似文献   

11.
采用等速测试和平衡测试方法,对我国优秀自由式滑雪空中技巧女子运动员的髋关节、膝关节屈肌力和伸肌力以及4种站姿下的静态平衡能力特征进行研究。结果表明髋关节右侧屈伸肌力、屈伸肌力比、平均功率值稍大于左侧屈肌力量,膝关节伸肌左、右侧单位体重峰力矩和左、右侧平均功率4个指标数值均大于屈肌,在60°/s（慢速）和240°/s（快速）不同的测试速度下,单位体重屈伸峰力矩、屈伸平均功率、屈伸肌力、平均功率随着测试速度的增加出现了显著性差异;正常双脚站立的平衡性大于单脚站立的平衡性。建议合理控制体重及均衡的训练肌肉力量,在适度提高运动速度的情况下,加强下肢伸肌力量的训练,为运动员进行针对性的力量训练、训练后肌肉效果的评价、运动员选材提供科学依据及有价值的理论参考。  相似文献   

12.
Abstract

The theory proposes a nonconscious mechanism that uses stored information (motor memory) to channel existing nervous impulses from brain waves and general afferent stimuli into the appropriate neuromotor coordination centers, subcenters, and efferent nerves, thus causing the desired movement. A consequent hypothesis requires that the simple reaction time will become longer when the response movement is required to be of greater complexity. Data obtained on college men and women, and 12- and 8-year-old boys, are in agreement with the hypothesis. Replacing a very simple finger movement with an arm movement of moderate complexity slows the reaction by about 20 percent; additional complexity produces a further slowing of 7 percent. The speed of the arm movement is considerably faster in college men than in younger boys or in college women. The correlation between reaction time and speed of movement averages approximately zero. Individual differences in ability to make a fast arm movement are about 70 percent specific to the particular movement being made; “general ability for arm speed” occurs only to the extent of 30 percent.  相似文献   

13.
Abstract

Previous studies on the kinematics of the golf swing have mainly focused on group analysis of male golfers of a wide ability range. In the present study, we investigated gross body kinematics using a novel method of analysis for golf research for a group of low handicap female golfers to provide an understanding of their swing mechanics in relation to performance. Data were collected for the drive swings of 16 golfers using a 12-camera three-dimensional motion capture system and a stereoscopic launch monitor. Analysis of covariance identified three covariates (increased pelvis–thorax differential at the top of the backswing, increased pelvis translation during the backswing, and a decrease in absolute backswing time) as determinants of the variance in clubhead speed (adjusted r 2 = 0.965, P < 0.05). A significant correlation was found between left-hand grip strength and clubhead speed (r = 0.54, P < 0.05) and between handicap and clubhead speed (r = ?0.612, P < 0.05). Flexibility measures showed some correlation with clubhead speed; both sitting flexibility tests gave positive correlations (clockwise: r = 0.522, P < 0.05; counterclockwise: r = 0.711, P < 0.01). The results suggest that there is no common driver swing technique for optimal performance in low handicap female golfers, and therefore consideration should be given to individual swing characteristics in future studies.  相似文献   

14.
The purpose of this study was to investigate the possible arm swing effect on the biomechanical parameters of vertical counter movement jump due to differences of the compliance of the take-off surface. Fifteen elite male beach-volleyball players (26.2 ± 5.9 years; 1.87 ± 0.05 m; 83.4 ± 6.0 kg; mean ± standard deviation, respectively) performed counter movement jumps on sand and on a rigid surface with and without an arm swing. Results showed significant (p < .05) surface effects on the jump height, the ankle joint angle at the lowest height of the body center of mass and the ankle angular velocity. Also, significant arm swing effects were found on jump height, maximum power output, temporal parameters, range of motion and angular velocity of the hip. These findings could be attributed to the instability of the sand, which resulted in reduced peak power output due to the differences of body configuration at the lowest body position and lower limb joints’ range of motion. The combined effect of the backward arm swing and the recoil of the sand that resulted in decreased resistance at ankle plantar flexion should be controlled at the preparation of selected jumping tasks in beach-volleyball.  相似文献   

15.
Abstract

The purpose of this study was to establish criterion-referenced standards for selected tests of arm and shoulder girdle strength and endurance for college females. Several popular tests of arm and shoulder girdle strength and endurance were administered to equal numbers of trained and untrained college females (N = 92) to generate data for the analysis. The contrasting groups method (Berk, 1976; Safrit & Wood, 1990) yielded the following criterion cutoff scores that classified college females as trained or untrained on the basis of regular upper arm and shoulder girdle resistance training: pull-ups = .5 repetitions (reps), 90° push-ups = 16 reps, flexed arm hang = 5s, seated chest press = 24.5 kg, seated biceps curl = 16.4 kg, seated lat pull (latissmus dorsi pull-down) = 38.2 kg, absolute strength index = 86.4 kg, and relative strength index = .6 kg per kg of body weight. Cross-validation of the standards on an independent sample of college females (N = 112) suggested stability of the cutoff scores for pull-ups, flexed arm hang, and relative strength.  相似文献   

16.
采用德国IsoMed 2000等速肌力测试仪,对17名健将（健将组）和18名一级（一级组）男子举重运动员进行双侧髋、膝和踝关节60°/s、120°/s、180°/s和240°/s向心、离心（每种角速度5次）测试。探讨优秀男子举重运动员下肢关节不同角速度等速肌力的特征,比较健将与一级组间差异,对健将组下肢关节相对峰力矩与相对专项成绩进行Pearson相关分析,并建立抓、挺举与峰力矩多元线性回归方程。结果显示,优秀男子举重运动员的髋关节相对伸爆发力与相对抓举呈高度显著正相关,髋关节中速（120°/s）、膝踝关节相对伸爆发力与相对抓举呈中度显著正相关,而踝关节相对屈绝对力呈中度显著负相关;髋关节相对伸爆发力与相对挺举呈高度显著正相关,左膝（挺举弓步腿）相对中速（120°/s）、爆发力和踝关节相对爆发力与相对挺举呈中度显著正相关。  相似文献   

17.
运用动态力学理论,建立单腿摆动力学模型和动力学方程,推导出人体在腾空阶段由于合理的肢体摆动使水平速度出现增量,从而证明人体重心在跳远腾空中的移动轨迹不是单质体空间运动轨迹,提出了由于肢体后直、前屈、速度快慢、力量大小的摆动而引起人体速度和位移变化的“动态抛物线”理论;并用加速度传感器测试系统测试运动的肢体摆动参数及身体在空中的速度变化,对“动态抛物线”理论进行了验证。这与传统的“起跳腾空后,身体重心运动轨迹在没有外力作用的情况下是不会改变的”理论迥然不同。利用这种理论,可以规范和完善跳远空中技术,提高教学质量和运动成绩  相似文献   

18.
Abstract

Previous studies have shown that the start plays a critical role in sliding events and explains more than 55% of the variance of the final time in luge. Experts evaluate the contribution of the arm strokes to be 23% of the total starting performance. The aim of the present study was to develop a measurement and feedback training tool (Speedpaddler) for the arm strokes of high-performance luge athletes. The construction is an aluminium alloy framework with a customary belt conveyor system, which is driven by two synchronized servo motors. Training is possible with constant speeds up to 12 m · s?1 or several speed curves, which simulate the acceleration of different luge tracks. The construction facilitates variations in the inclination and speed of the conveyor belts and thereby the resistance and movement speed. If the athlete accelerates the conveyor belts during arm-paddling, the torque of the motors decreases. Torque measurements and high-speed video offer valuable insights into the several technique criteria. Comparisons of arm-paddle cycle durations on ice and on the Speedpaddler with 18 luge athletes (national team and juniors) showed no statistical differences. The Speedpaddler might be a useful tool to improve starting performance all year round.  相似文献   

19.
ABSTRACT

The skating acceleration to maximal speed transition (sprint) is an essential skill that involves substantial lower body strength and effective propulsion technique. Coaches and athletes strive to understand this optimal combination to improve performance and reduce injury risk. Hence, the purpose of this study was to compare body centre of mass and lower body kinematic profiles from static start to maximal speed of high calibre male and female ice hockey players on the ice surface. Overall, male and female skaters showed similar centre of mass trajectories, though magnitudes differed. The key performance difference was the male’s greater peak forward skating speed (8.96 ± 0.44 m/s vs the females’ 8.02 ± 0.36 m/s, p < 0.001), which was strongly correlated to peak leg strength (R 2 = 0.81). Males generated greater forward acceleration during the initial accelerative steps, but thereafter, both sexes had similar stride-by-stride accelerations up to maximal speed. In terms of technique, males demonstrated greater hip abduction (p = 0.006) and knee flexion (p = 0.026) from ice contact to push off throughout the trials. For coaches and athletes, these findings underscore the importance of leg strength and widely planted running steps during the initial skating technique to achieve maximal skating speed over a 30 m distance.  相似文献   

20.
Whole body vibration (WBV) is used as a training method but its physical risk is not yet clear. Hence, the aim of this study is to assess the exposure to WBV by a measure of acceleration at the lower limb under dynamic and static postural conditions. The hypothesis of this paper is that this assessment is influenced by the frequency, position, and movement of the body. Fifteen healthy males are exposed to vertical sinusoidal vibration at different frequencies (20–60 Hz), while adopting three different static postures (knee extension angle: 180°, 120° and 90°) or performing a dynamic half-squat exercise. Accelerations at input source and at three joints of the lower limb (ankle, knee, and hip) are measured using skin-mounted accelerometers. Acceleration values (g) in static conditions show a decrease in the vibrational dose when it is measured at a more proximal location in the lower extremity. The results of the performed statistical test show statistically significant differences (p < 0.05) in the transmissibility values caused by the frequency, the position, and to the presence of the movement and its direction at the different conditions. The results confirm the initial hypothesis and justify the importance of a vibration assessment in dynamic conditions.  相似文献   

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