青少年男子短跑运动员膝关节等速肌力特征研究

目的：通过对36名二级青少年男子短跑运动员双侧膝关节进行等速测试，探析青少年短跑运动员膝关节向心屈伸肌群的生物力学特性．为运动训练、科学选材及临床康复等提供理论依据。方法：利用Kinitech等速康复肌力测试系统对青少年男子短跑运动员膝关节屈伸肌群进行等速测试。结果：青少年男子短跑运动员双侧膝关节屈伸峰力矩随测试速度的增加呈递减趋势，且膝伸肌大于膝屈肌（P〈0．05），峰力矩屈伸比（V／E）随给定测试速度的增加呈递增趋势；最大功率随测试速度的增大而增加，同一测试速度下屈、伸肌群最大功率无明显差异，左、右侧相比也无显著性差异（600／s伸肌除外）；屈伸肌群达峰力矩的角度（APT）表现为伸肌角度明显低于屈肌角度，随速度增加左右两侧膝关节达峰力矩的角度无显著差异：双侧膝关节屈伸肌群达峰力矩的时间（TPT）随测试速度的增加而减小，同一测试速度下伸肌达峰力矩的时间大于屈肌；右侧膝关节屈肌相对峰力矩（PT／BM）与下肢形态学指标表现出不同程度的正相关。结论：青少年男子短跑运动员膝关节峰力矩变化规律与成年人相一致，但左右侧膝关节屈伸肌群做功能力发展不平衡，屈伸肌群运动达峰力矩角度、达峰力矩的时间存在显著差异。     

上海优秀男子青少年中跑运动员髋、膝关节等速肌力测试分析

通过对男子青少年中跑运动员进行髋、膝关节等速肌力测试,发现男子青少年中跑运动员髋、膝关节肌力特点及薄弱肌群。方法：对16名上海优秀男子青少年中跑运动员进行髋、膝关节单侧等速向心60°／s×6和240°／s×6测试记录测试峰力矩、最大功率、屈伸肌峰力矩比值。结果：髋关节屈肌峰力矩和相对峰力矩在两个速度存在显著差异（P〈0．05）,伸肌峰力矩和相对峰力矩两个速度存在高度显著差异（P〈0．01）,屈伸肌峰力矩比值存在显著差异（P〈0．05）,膝关节屈肌峰力矩及相对峰力矩无差异,而伸肌峰力矩和相对峰力矩在两个速度存在显著差异（P〈0．05）,屈伸肌峰力矩比值无差异。研究对象髋关节屈肌最大功率和相对最大功率在两个速度存在高度显著差异（P〈0．01）,伸肌最大功率和相对最大功率存在显著差异（P〈0．05）,膝关节屈伸肌最大功率和相对最大功率在两个速度存在高度显著差异（P〈0．01）。结论：髋关节随测试速度增加最大力矩呈现下降趋势,高速测试时峰力矩屈／伸值下降,髋关节屈肌力量需加强;膝关节伸肌峰力矩随测试速度增加减小,屈肌及峰力矩屈／伸值变化不明显。     

青少年男子篮球运动员膝关节等速肌力特征研究

通过对36名二级青少年男子篮球运动员双侧膝关节进行等速测试,探析青少年篮球运动员膝关节向心屈伸肌群的生物力学特性,为运动训练、科学选材及临床康复等提供理论依据.方法:利用 Kinitech等速康复肌力测试系统,对青少年男子篮球运动员膝关节屈伸肌群进行等速测试.结果表明:青少年男子篮球运动员双侧膝关节屈伸峰力矩随测试速度的增加呈递减趋势,且膝伸肌大于膝屈肌(P<0.05),峰力矩屈伸比(F/E)随给定测试速度的增加呈递增趋势;最大功率随测试速度的增大而增加,同一测试速度下屈、伸肌群最大功率无明显差异,左、右侧相比也无显著性差异(60°/s伸肌除外);屈伸肌群达峰力矩的角度(APT)表现为伸肌角度明显低于屈肌角度,随速度增加左右两侧膝关节达峰力矩的角度无显著差异;双侧膝关节屈伸肌群达峰力矩的时间(TPT)随测试速度的增加而减小,同一测试速度下伸肌达峰力矩的时间大于屈肌;右侧膝关节屈肌相对峰力矩(PT/BM)与下肢形态学指标表现出不同程度的正相关.本研究结论,青少年男子篮球运动员膝关节峰力矩变化规律与成年人相一致,但左右侧膝关节屈伸肌群做功能力发展不平衡,屈伸肌群运动达峰力矩角度、达峰力矩的时间存在显著差异.     

小学生双侧膝关节等速肌力特征研究

目的:通过对6 3名普通小学生双侧膝关节进行等速测试,探讨少儿人群膝关节屈伸肌的生物力学特性。方法:利用Kinitech等速测力系统对健康男、女小学生双侧膝关节屈伸肌群进行等速测试。结果:小学男、女生双侧膝关节屈伸峰力矩(PT)随测试速度的增加呈递减趋势,且膝伸肌大于膝屈肌,男、女屈伸峰力矩有显著差异(6 0°/s屈肌除外) ,且表现为同一速度下男生峰力矩大于女生(P <0 .0 5 ) ;膝关节屈伸最大功率(MP)随测试速度的增加呈递增趋势,男、女小学生之间存在显著差异(2 4 0°/s伸肌除外) ;男、女小学生膝关节屈伸肌力比(F/E)不存在性别差异,同一测试速度下左右屈伸F/E不存在显著差异(P >0 .0 5 ) ,但F/E比值接近1,明显高于成年人;小学男生左、右膝关节屈伸PT/BM和小腿长呈高度相关(r介于0 .4 5～0 .70 ) ,女生大腿围度与PT/BM具有不同程度的相关。结论:以小学生为代表的少儿人群膝关节的屈伸肌力特征与成年人总体趋势基本一致,但在屈伸肌力比(F/E)及男、女性别差异等方面与成年人存在差异。     

我国优秀青少年女子跳高运动员膝关节等速肌力特征研究

通过对18名二级以上青少年女子跳高运动员左右两侧膝关节进行等速测试,探析青少年跳高运动员膝关节向心屈伸肌群的生物力学特性,为运动训练、科学选材及临床康复等提供理论依据。利用Kinitech等速肌力测试系统对青少年女子跳高运动员膝关节进行等速肌力测试,发现青少年女子跳高运动员双侧膝关节屈伸肌群等速向心收缩时的峰力矩随运动速度的增大(60°/s→240°/s)呈减小趋势,在60°/s和120°/s测试速度下同侧肌群表现为伸肌峰力矩明显大于屈肌峰力矩(P<0.05),而240°/s测试速度下则反之,同一测试速度下,左、右侧膝关节屈肌群峰力矩具有显著性差异(P<0.01),峰力矩屈伸比(F/E)随运动速度的增加呈增大的趋势;最大功率随运动速度的增大而增加,同一测试速度下屈肌群与伸肌群最大功率无明显差异(60°/s伸肌除外),达峰力矩的角度表现为伸肌明显低于屈肌,并随运动速度的增加有增大趋势,而伸肌有减小趋势。达峰力矩的时间表现为随速度的增加而减小的趋势,同一测试速度下表现出伸肌大于屈肌;相对峰力矩只有在240°/s运动速度下与大小腿比例(D/X)呈高度负相关。得出结论,青少年女子跳高运动员膝关节屈伸峰力矩变化规律与成年人基本一致,但双侧膝关节屈伸肌群做功能力较弱,应加强下肢肌群的速度力量练习。     

优秀攀岩运动员肘关节屈伸肌等速肌力测试研究

利用德国Isomed2000等速肌力测试系统对优秀攀岩运动员左右肘肘关节进行等速测试,探析攀岩运动员肘关节屈伸肌群的生物力学特征,为运动训练科学选材及康复提供理论依据。结果：优秀攀岩运动员屈伸峰力矩（PT）随测试速度的增大而减小,且屈伸峰力矩屈肌大于肘伸肌;最大功率随测试速度的增大而增加,左右侧做功无明显差异,表明两侧肌力平衡;屈或伸的向心/离心（ECC/CON）随给定运动速度的增加而增大,屈肌的向心/离心（ECC/CON）比值小于1.0。     

女子柔道运动员上肢肌肉力量变化特征的研究

用ＣＹｂｅｘⅡ＋等动测力系统对１３名女子柔道运动员上肢肘关节屈伸肌群分别进行最大等长测试（肘关节９０（°）屈位、６０（°）／ｓ慢速测试、１２０（°）／ｓ、２４０（°）／ｓ快速测试及耐力测试。结果发现，最大等长力量屈肌大于伸肌（Ｐ＜０．０５）。随测试速度增加屈伸肌力量下降，并且快速力量下降幅度较大。不同速度下屈伸肌表现出的最大力量相差不大（Ｐ＞０．０５），屈伸肌力比基本平衡。屈伸肌耐力存在较大差别，伸肌耐力明显高于屈肌（Ｐ＜０．００１）。伸肌产生最大肌力时的肘关节角度受环节速度的影响，随速度加快其最大肌力出现在收缩过程的后期。     

我国优秀划艇运动员肩、肘关节肌力特征的比较研究

运用等速测试系统对备战伦敦奥运会的国家划艇运动员的肩关节、肘关节肌力进行测试与分析。结果表明:1)从力矩角度来看,优秀运动员与一般运动员在肩、肘关节肌力特征中存在显著性差异(P<0.05),且屈肌和伸肌的力矩角度分别呈现不同的特征;2)从峰力矩比值来看,在不同速度运动下,国家队优秀运动员和一般运动员均存在屈伸比的失衡问题,即最大力量上存在屈伸肌群发展的不合理化现象(<50%),随着测试速度的增加,屈伸比呈递减趋势;3)在肘关节两侧同名肌群的比较中同样存在不均衡现象,尤其是伸肌的两侧差值较大;4)肩关节的肌力特征也存在类似的现象,但屈肌明显不如伸肌力量。结论:应逐步加强划艇运动员肩、肘关节同侧屈伸肌群和异侧同名肌群的力量均衡性训练,并提高肩关节的屈肌力量能力。     

不同等级散打运动员肘、膝关节肌群等速测试肌力特征研究

结合训练实践,运用ISOMED2000等速测试仪对我国男子散打主力队员膝、肘关节屈伸肌群肌力特征进行测试与分析。结论:不同等级散打运动员肘关节屈伸肌群等速向心、离心收缩、膝关节伸肌群等速离心收缩相对峰力矩值在60°/s、180°/s时具有显著性差异(P<0.05);膝关节屈伸肌群等速向心收缩、屈肌群离心收缩相对峰力矩值在各角速度下具有显著性差异(P<0.05);不同等级散打运动员肘、膝关节屈伸肌群等速向心收缩在300°/s、离心收缩在240°/s时达到力矩梯度最大值,且差异显著。说明基础力量、中快速力量及快速动作爆发力能较好地反映专项运动水平,相对峰力矩、力矩梯度数值越大,专项水平越高。     

自由式滑雪空中技巧国家队运动员膝关节屈伸肌群肌肉力量特征

目的：为了观察我国自由式滑雪空中技巧队男女运动员下肢膝关节屈伸肌群力量特点,发现目前下肢力量训练中存在的问题,以便为力量训练提供参考依据。方法：使用美国BIODEX公司生产的biodex system4等动测试系统对自由式滑雪空中技巧队男女运动员（男5名,女6名）的下肢膝关节屈伸肌群进行向心收缩的等动测试,测试速度分别为60°/s和180°/s。结果：男女运动员伸肌群的相对峰值力矩和相对平均功率都要显著高于屈肌群（P<0.01）。相对峰值力矩随着测试速度的增加而显著减小（P<0.01）,相对平均功率随测试速度的增加而显著增加（P<0.01）。男女运动员下肢屈伸肌比平均在50%～65%之间,并且随着测试速度的增加屈伸肌比显著增加（P<0.05）。在同一速度下,男女运动员伸肌峰值力矩出现的角度要显著大于屈肌（P<0.01）,但是在不同速度下,男女运动员伸肌峰值力矩出现的角度表现出不同的变化。随着测试速度的增加,屈伸肌群峰值力矩出现的时间显著变短（P<0.01）,并且同一速度下,屈肌群峰值力矩出现的时间要短于伸肌群（P<0.05）。左右腿膝关节屈伸肌群相对峰值力矩、相对平均功率、屈伸肌比等指标没有差异（P>0.05）。结论：了解到目前我国自由式滑雪空中技巧队男女运动员下肢肌肉的力量特点,其中男女运动员下肢膝关节屈伸肌比（H/Q）较低,应该注重发展股后肌群的力量,以提升屈伸肌比值。左右腿肌肉力量发展比较均衡。     

Isokinetic imbalance of hip muscles in soccer players with osteitis pubis

Abstract

In this study, we compared the isokinetic torques of hip flexors/extensors and abductors/adductors in soccer players suffering from osteitis pubis (OP), with normal soccer players. Twenty soccer male athletes with OP and 20 normal soccer athletes were included in this study. Peak torque/body weight (PT/BW) was recorded from hip flexor/extensor and abductor/adductor muscles during isokinetic concentric contraction modes at angular velocity of 2.1 rad · s^?1, for both groups. The results showed a significant difference between the normal and OP groups for hip flexors (P < 0.05). The normal group had significant, lower PT/BW value than the OP group for their hip flexors (P < 0.05). The hip flexor/extensor PT ratio of OP affected and non-affected limbs was significantly different from that of normal dominant and non-dominant limbs. There were no significant differences between the normal and OP groups for hip extensor, adductor and abductor muscles (P > 0.05). Regarding the hip adductor/abductor PT ratio, there was no significant difference between the normal and OP groups of athletes (P > 0.05). The OP group displayed increase in hip flexor strength that disturbed the hip flexor/extensor torque ratio of OP. Therefore, increasing the hip extensor strength should be part of rehabilitation programmes of patients with OP.     

Effects of regular training at the same time of day on diurnal fluctuations in muscular performance

The aim of this study was to determine whether there is an effect of time of day on the adaptation to strength training at maximal effort. Fourteen participants took part in this experiment. Their peak anaerobic power (Wingate anaerobic test) and peak knee extension torque at six angular velocities (1.05, 2.10, 3.14, 4.19, 5.24 and 6.29 rad · s -1 ) were recorded in the morning (between 07:00 and 08:00 h) and in the evening (between 17:00 and 18:00 h) just before and 2 weeks after a 6 week course of regular training. Seven of them trained only in the morning and seven only in the evening. Multivariate analysis of variance revealed a significant group 2 pre-/post-training 2 time of day interaction effect for peak torque and peak anaerobic power. Before training, in both groups, peak torque and peak anaerobic power were significantly higher in the evening than in the morning. After training, there was no significant difference in peak torque and peak anaerobic power between the morning and the evening for the morning training group. In contrast, in the evening training group, peak torque and peak anaerobic power were higher in the evening than in the morning. As a result of training, both peak torque and peak anaerobic power increased from their initial values as expected. The morning training group improved their peak anaerobic power significantly in the morning and in the evening, the absolute increase being larger in the morning than in the evening. The evening training group did not improve their peak anaerobic power in the morning, whereas it improved significantly in the evening. Although peak torque was significantly improved by training in the morning and evening in both groups, the absolute increase was greater in the morning than in the evening in the morning training group, whereas the opposite was the case for the evening training group. These results suggest that training twice a week at a specific hour increases the peak torque and the peak anaerobic power specifically at this hour and demonstrates that there is a temporal specificity to strength training.     

男子跳远运动员膝关节肌等速向心收缩的肌力研究

利用cybex-770等速测试与康复系统,对17名一级男子跳远运动员起跳腿的膝关节进行了等速向心收缩测试。所测试的指标包括相对峰力矩、相对总功、相对平均功率、峰力矩屈伸比等,对这些指标进行综合分析,并且结合跳远运动项目下肢肌最大力量和爆发力的项目特点,为优秀运动员有针对性的力量训练提供参考依据。     

The relationship between strength asymmetries and jumping performance in professional volleyball players

Knee peak torque (PT) is associated to jump performance in volleyball players. It is not clear whether muscle strength imbalances of the knee joint can influence jump performance. The purpose of study was to analyse the association between PT and knee muscular imbalances with jump performance in professional volleyball players. Eleven elite male volleyball players (90.3 ± 9.7 kg body mass and 1.94 ± 0.06 m height) were evaluated in an isokinetic dynamometer at speeds of 60, 180 and 300 deg/s. Muscle strength imbalances were obtained through calculation of contralateral deficit between limbs and the conventional ratio (hamstrings/quadriceps). Countermovement jump (CMJ) was performed on a force plate to calculate mechanical power and height. Association was found between knee extensor PT at 180 deg/s with CMJ power (r = 0.610, p = 0.046). Conventional ratio at 300 deg/s showed negative association with CMJ (r = ?0.656, p = 0.029). The optimal ratio between knee extensors PT in relation to the flexors PT is associated with the greater mechanical power in CMJ. Contralateral deficit does not seem to be associated with the CMJ performance. Considering the knee extensor PT is associated with CMJ power, our findings suggest that strength-based training in volleyball athletes should not omit the conventional muscle ratio.     

我国运动员血清T/E_2、T/F水平的研究

本文测定了200多名不同年龄的省级以上运动员及普通人的血清事酮(T)、雌二醇(E_2)、皮质醇(F)的基础值,对体内激素平衡T/E_2及T/F值进行了相关分析,根据不同运动项目、年龄及训练年限与普通人进行了对比分析,研究结果表明:男、女性运动员T/E_2平均比值比普通人高(P<0.01);T/F均值比普通人高(P<0.05)。青少年男、女运动员以15～16岁组T/E_2、T/F为较大差异期(P<0.01)。不同项目其T/E_2与T/F均值有显著差异(P<0.05,P<0.01)。提示T/E_2与T/F将成为运动员选材、机能评定、疲劳恢复及激素治疗的重要内分泌激素指标的参考依据。     

Discrimination of Visual Linear Velocities

Abstract

The purpose of the present study was to determine velocity discrimination characteristics of subjects in a difference threshold paradigm. After recruitment, 180 male and female subjects were randomly assigned to 1 of 6 groups differentiated by the length of the stimulus runway and the subjects' orientation to the stimulus. Stimulus velocities were presented on a modified Bassin Anticipation Timer with presentation rate controlled by a programmed timer. The criterion velocities were 134.11, 268.22 and 402.33, cm/sec with variable velocities ranging 44.7 cm/sec above and below the criterion in 8.94 cm/sec increments. The method of constant stimuli was used with 198 trial pairs presented (constant 7 second stimulus presentation interval). The results indicated that the discrimination of horizontal linear velocity follows a prothetic continuum. That is, the just noticeable difference increased in proportion to the increase in the criterion velocity. In addition, the subjects' orientation to the stimulus and the viewing distance (length of runway) seemed to play little or no role in the discrimination process.     

The effect of load and sex on kinematic and kinetic variables during the mid-thigh clean pull

Power is a fundamental component for many sporting activities; while the load that elicits peak power during different exercises and differences between sexes remains unclear. This study aims to determine the effect of sex and load on kinematic and kinetic variables during the mid-thigh clean pull. Men (n = 10) and women (n = 10) performed the mid-thigh clean pull at intensities of 40%, 60%, 80%, 100%, 120%, and 140% of one repetition maximum (1RM) power clean in a randomised and counter-balanced order, while assessing bar velocity, bar displacement, power, force, and impulse. Two-way analysis of variance revealed that men demonstrated significantly greater (p < 0.05) values for all variables across loads, excluding bar velocity. Men demonstrated significantly greater (p < 0.05) bar velocities with 40–80% 1RM; in contrast, women demonstrated significantly (p < 0.05) higher velocities with 120–140% 1RM. Irrespective of sex significantly greater (p < 0.05), system peak power, bar velocity, and displacement occurred with 40% 1RM. In contrast, peak force and impulse were significantly (p < 0.05) greater with 140% 1RM. When performing the mid-thigh clean pull, to maximise system power or bar velocity, lower loads (40–60% 1RM) are recommended. When training force production or impulse, higher loads (120–140% 1RM) are recommended, when using the mid-thigh clean pull.     

人体静态不同体位对颈总动脉血流最大流速影响

目的：研究青年人群、中年人群和老年人群在静态下不同体位颈总动脉血流最大流速的特征。方法：选取安庆师范大学165名志愿者,采用Philps Color Doppler CV850彩色超声,对18~25岁(不含25)、25~59岁(含59)以及59岁以上3个年龄段不同性别的人群在4种体位状态下颈总动脉血流最大流速进行测量。结果：右侧颈总动脉：性别相同时,青年男性组和中年男性组、青年女性组和老年女性组在直立位上具有非常显著性差异;中年男性组和老年男性组在仰卧位上具有非常显著性差异;青年女性组和中年女性组在头低位-30°上具有非常显著性差异。左侧颈总动脉：年龄相同时,中年男性组和中年女性组在仰卧位上具有非常显著性差异,中年男性组和中年女性组在头低位-90°上具有非常显著性差异;性别相同时,中年女性组和老年女性组在直立位上具有非常显著性差异;中年男性组和老年男性组在头低位-30°上具有非常显著性差异。结论：无论男女,随年龄的增大颈总动脉血流最大流速减慢;体位由仰卧位、直立位、头低位-30°、头低位-90°的顺序变化,颈总动脉血流最大流速减慢;同年龄段,颈总动脉血流最大流速男性均高于女性。