Electromyography and the study of sports movements: A review

Within electromyography (EMG), a particular speciality has been developed wherein the aim is to use EMG for the study of muscular function and co‐ordination. This area of research is usually called kinesiological EMG. The general aims of kinesiological EMG are to analyse the function and co‐ordination of muscles in different movements and postures, in healthy subjects as well as in the disabled, in skilled actions as well as during training, in humans as well as in animals, under laboratory conditions as well as during daily or vocational activities. This is often done by a combination of electromyographical and kinesiological or biomechanical measurement techniques.

Because there are over 400 skeletal muscles in the human body and both irregular and complex involvement of the muscles may occur in neuromuscular diseases and in voluntary occupational or sports movements, it is impossible to sample all of the muscles of the entire body during the performance of complex motor skills. In addition, the measurement of kinesiological EMG in sport and specific field circumstances, such as the track and/or soccer field, the alpine ski slope, the swimming pool and the ice rink, demands a specific technological and methodological approach, adaptable to both the field and the sport circumstances.

Sport movement techniques and skills, training approaches and methods, ergonomic verification of the human‐machine interaction have, amongst others, a highly specialized muscular activity in common. The knowledge of such muscular action in all its aspects, its evaluation and its feedback should allow for the optimization of movement, of sports materials, of training possibilities and, in the end, of sports performance.

Drawing conclusions from a review of the EMG research of 32 sports, covering over 100 different complex skills, including methodological approaches, is an impossible task. We have attempted to set standards concerning the EMG methodology at the beginning of this review. Electromyography and sports is a vast area and a complete review is impossible, as information will be found scattered in many different journals, including those on the sports sciences, ergonomics, biomechanics, applied physiology, in different congress proceedings, and so on. Consequently, many important aspects and possibly important publications may have been omitted from this review.     

The relationship between muscle cross-sectional area and strength in various isokinetic movements among soccer players

Abstract

The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad·s^?1 (3.14 rad·s^?1) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P<0.05–0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r<0.26, n.s.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r=0.38–0.64, P<0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength—CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players.     

Functional shoulder ratios with high velocities of shoulder internal rotation are most sensitive to determine shoulder rotation torque imbalance: a cross-sectional study with elite handball players and controls

The aim of the present study was to determine which approach to calculating shoulder ratios is the most sensitive for determining shoulder torque imbalance in handball players. Twenty-six participants (handball athletes, n = 13; healthy controls, n = 13) performed isokinetic concentric and eccentric shoulder internal rotation (IR) and external rotation (ER) assessment at 60, 180 and 300°/s. We used eight approaches to calculating shoulder ratios: four concentric (i.e. concentric ER torque divided by concentric IR torque), and four functional (i.e. eccentric ER torque divided by concentric IR torque) at the velocities of 60, 180 and 300°/s for both IR and ER, and combining 60°/s of ER and 300°/s of IR. A three factorial ANOVA (factors: shoulder ratios, upper limb sides, and groups) along with Tukey’s post-hoc analysis, and effect sizes were calculated. The findings suggested the functional shoulder ratio combining 60°/s of ER and 300°/s of IR is the most sensitive to detect differences between upper limbs for handball players, and between players and controls for the dominant side. The functional shoulder ratio combining 60°/s of ER with 300°/s of IR seems to present advantages over the other approaches for identifying upper limb asymmetries and differences in shoulder torque balance related to throwing.     

基于准稳态信号的动态肌肉疲劳表面肌电信号变化特征

目的:改进非稳态sEMG信号的分析方法,探讨动态肌肉疲劳表面肌电信号变化特征。方法:12名男性被试进行40次180°/sec肘关节等速屈伸运动,记录肱二头肌sEMG信号,将主动收缩期和拮抗收缩期信号进行分离和重组处理,计算并观察未处理前原始信号、处理后主动收缩期及拮抗收缩期信号的线性指标AEMG、MPF和非线性指标C(n)、DET%变化。结果:处理后的sEMG信号基本符合稳态信号的特征;处理后主动收缩期sEMG信号指标MPF、C(n)和DET%与屈肘峰力矩之间的相关性较之处理前均有不同程度的增加,其中,DET%与屈肘峰力矩相关的增加非常显著;主动收缩期和拮抗收缩期MPF、C(n)与DET%变化趋势一致,肱二头肌作为主动肌收缩时sEMG信号的C(n)较低,而作为拮抗肌收缩时C(n)则较高。结论:传统对静态sEMG信号进行连续分析的方法不适于动态sEMG信号。对动态sEMG信号进行适当的分离组合处理,可获得更为准确的分析结果。     

Functional torque ratios and torque curve analysis of shoulder rotations in overhead athletes with and without impingement symptoms

Abstract

In this study, we evaluated the peak torque, functional torque ratios, and torque curve profile of the shoulder rotators in overhead athletes with impingement symptoms so as to examine possible alterations in response to sports training and shoulder pain. Twenty-one overhead athletes with impingement symptoms were compared with 25 overhead athletes and 21 non-athletes, none of whom were symptomatic for impingement. The participants performed five maximal isokinetic concentric and eccentric contractions of medial and lateral shoulder rotations at 1.57 rad · s^?1 and 3.14 rad · s^?1. Isokinetic peak torque was used to calculate the eccentric lateral rotation-to-concentric medial rotation and the eccentric medial rotation-to-concentric lateral rotation ratios. An analysis of the torque curve profiles was also carried out. The eccentric lateral rotation-to-concentric medial rotation torque ratio of asymptomatic athletes was lower than that of non-athletes at both test velocities. The concentric medial rotation isokinetic peak torque of the asymptomatic athletes, at 3.14 rad · s^?1, was greater than that of the non-athletes, and the peak appeared to occur earlier in the movement for athletes than non-athletes. These findings suggest that there may be adaptations to shoulder function in response to throwing practice. The eccentric medial rotation-to-concentric lateral rotation torque ratio was altered neither by the practice of university-level overhead sports nor impingement symptoms.     

优秀水球运动员膝关节肌群等速向心收缩力量特征研究

利用等速测试及康复系统对优秀水球运动员膝关节肌群进行等速向心收缩测试与分析,结果发现,峰力矩可作为评价水球运动员膝关节肌力大小的一个敏感指标,峰力矩值越大,肌肉做功能力越强,做功效率越高。水球运动员膝关节慢速肌力与快速肌力呈非常显著相关,其左右膝关节肌力相当平衡,快速屈伸肌比率大于慢速屈伸肌,屈肌的慢速力量较弱。     

立定跳远落地姿态的合理性

对30名受试者正常和“外八”两种落地姿态立定跳远成绩、走路步向角、踝关节内收、外展等动肌力测试,探讨“外八”姿态落地对立定跳远成绩的影响。结果发现：与正常姿态落地相比,立定跳远采用“外八”姿态落地对落地后身体稳定性的影响差异不具显著性;两种落地姿态的立定跳远成绩差异没有显著性;采用外八字姿态落地,50%(男8人,女7人)成绩下降,幅度为0.05 m,33.3%(男4人,女6人)成绩上升,幅度为0.07 m,百分率和升降幅度差异均不具显著性;采用外八字姿态落地立定跳远成绩升降幅度与步向角,踝关节快、慢速外展最大幅度均中等程度相关(P<0.05)。结果说明：与正常落地姿态相比,外八字落地姿态立定跳远的成绩升或降因人而异,与受试者步向角,踝关节快、慢速外展的最大幅度呈中等程度相关,步向角越小,踝关节外展最大幅度越大,采用外八字姿态落地立定跳远的成绩提高的几率越大。     

优秀投掷运动员核心力量等速肌力测试研究

目的:分析浙江师范大学投掷训练队优秀运动员腰背肌的生物力学特征,探讨投掷运动员的成绩与腰背屈伸肌群力量的关系,为投掷训练和易受伤部位的预防提供理论依据。方法:利用德国Isomed2000等速肌力测试系统进行核心力量等速肌力测试,测试严格按照Isomed2000等速测试系统使用手册的要求进行操作。结果:优秀投掷运动员腰背屈伸肌群等速向心收缩峰力矩随测试速度(30°/s~180°/s)的增加大体呈递减趋势,且随着角速度的增大,优秀投掷运动员的腰背屈伸肌群等速向心收缩峰力矩下降幅度(斜率K:伸-0.884小于屈-0.655)比普通人(K:伸-0.275小于屈-0.035)小,且优秀投掷运动员伸肌最大峰力矩的下降幅度要比屈肌小;在角速度为30°/s到120°/s时,最大功率随着给定角速度的增大而增大,在180°/s时又有所减小;腰背屈伸肌群峰力矩的角度在30°/s到180°/s时伸肌55.5°~58°大于屈肌的54.5°~56.25°,随着角速度的增大,大体呈上升趋势,在30°/s时峰力矩角度最小。     

竞技舞龙运动员肩关节屈伸肌群等速肌力特征研究

采用文献资料法、专家访谈法、测试法、数理统计法,探讨和研究了舞龙运动员等速运动状态下肩关节屈伸肌群的力学特征以及肌力的相互关系。结果表明:舞龙运动员肩关节屈伸肌的峰值力矩和相对峰力矩随着测试角速度的增加而下降;且左侧肩关节屈伸肌的峰值力矩和相对峰力矩均大于另一侧;肩关节屈伸肌峰力矩和相对峰力矩值均表现为伸肌群明显大于屈肌群;肩关节伸肌的峰力矩均大于屈肌的峰力矩;伸肌群的平均功率也明显大于屈肌群的平均功率。     

优秀男子举重运动员专项成绩与下肢等速肌力相关回归分析

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。     

等动训练促进运动员膝关节术后肌肉力量恢复的研究

为探讨等动训练对促进运动员膝关节术后肌肉力量恢复的应用价值，采用了美国产CYBEX770等动力系统对3名膝关节术后运动员进行膝关节肌肉4周力量恢复训练。结果表明，等动训练后运动员膝关节肌肉力量明显提高，提示等动训练对促进运动员膝关节术后肌肉力量恢复具有良好的效果。     

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。     

优秀女子自行车运动员踝关节肌群等动向心测试研究

利用等动测力系统(Cybex-6000)对10名优秀女子自行车运动员进行踝关节肌力的等动向心测试。研究的结果表明:1)踝关节肌群等动向心收缩时峰力矩及相对峰力矩随运动速度的增加而减少,总功及相对总功随测试速度的增加而减小,而平均功率及相对值随测试速度的增加而增大;2)踝关节前后侧肌力矩相差很大,而且显示出速度的差异性。自行车运动员踝关节肌群的肌力特征,反映了踝关节的肌肉配布与踝关节肌群的训练特征,体现了其合肌肉规律,合肌群特色,合运动实际的规律。     

排球运动员下肢肌力与肌电特征的相关研究

采用实验法,通过美国产艾力尔智能化力量诊断与训练系统(ACES)和芬兰产Megawin6000肌电仪相结合,探索排球运动员下肢膝关节等速运动状态下肌力、肌电特征以及二者的相互关系,为应用积分肌电评价排球运动员专项力量素质奠定基础,为设计专项力量训练方法、预防运动损伤提供科学依据。研究结果表明排球运动员膝关节等速肌力特征符合Hill方程和力速曲线关系;膝关节等速测试运动期间采集到的股四头肌肌电信号可以客观地评价积分肌电与肌力指标之间的关系,指导专项力量训练实践。     

一侧肢体等动力量训练对异侧肢体力量的影响

通过对大学生长时间一侧肢体等动力量训练后,测定该侧和对侧肢体的力量变化,探索一侧肢体运动后对对侧肢体影响的生理效应。为以单侧肢体运动为主的运动项目产生的身体效应,单侧肢体损伤后的康复训练方案的确定以及力量迁移现象的证实提供实验依据。     

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。     

对踝关节主要屈伸肌群sEMG测量标准化验证研究

通过高速摄影、表面肌电图（sEMG）测量以及等速肌力测试等方法对12名体育专业男生进行研究,获取踝关节主要屈伸肌（胫骨前肌和腓肠肌）等速肌力与sEMG之间的关系,以此说明用sEMG来直接评价肌肉用力情况时需进行标准化的必要性及最佳标准化方式。结果表明：相同肌肉收缩过程中,肌力矩值与平均振幅（MA）的变化趋势呈现高度相关,相关系数r在0.6以上;不同收缩形式、不同收缩速度下,均方根振幅（RMS）、积分肌电（iEMG）值会随着收缩速度的增加而减小;跳深动作下肢肌肉sEMG标准化后的值与跳深腾起速度之间均有一定的相关性,标准化后以最大随意等长收缩（MVIC）的标准化值与跳深腾起速度的相关性最高。     

短跑专项力量训练手段训练效应的实证研究——以拖重物跑为例

研究目的：探究拖重物跑训练手段对短跑运动员的身体素质、途中跑阶段的技术特征及下肢环节肌肉力量的影响，深入认识其对短跑途中跑技术和专项力量的作用机制。研究方法：对14名男子二级左右水平短跑运动员进行为期8周每周3次6%~10% BM负荷的拖重物跑训练，采用高速摄像分析法、等动肌力测试法分析运动员身体素质；支撑阶段髋、膝、踝关节运动学参数和下肢各环节肌肉力量实验前后的变化情况。结果：（1）实验后运动员30m、60m、立定跳远、立定三级跳远等身体素质及专项成绩显著提高；（2）步长、重心水平速度显著性提高，两大腿剪绞平均速度提高、单步时间减少；支撑阶段最小膝、踝角显著降低，角速度提高；（3）髋、膝关节伸/屈肌群PT/BW、AP除膝关节60°/sPT/BW值未见统计学意义，其余各角速度下PT/BW、AP均呈显著性差异，踝关节跖屈肌群各角速度下PT/BW值显著提高，跖屈肌群60°/s速度下AP提高，背屈肌群AP略降低。结论：适宜负荷的拖重物跑训练可显著改善短跑运动员运动素质、提高运动成绩；有利于提高髋关节剪绞-制动力量，使膝、踝关节处于低位超等长"屈蹬"状态；提高了髋、膝关节屈伸肌群快速主动收缩能力及踝关节跖屈肌群退让性快速收缩能力。     

青年大学生动态等速肌力性别差异的实验研究

40名健康男、女大学生参加本项研究 ,动态等速肌力测试包括肘和膝关节的屈伸运动 ,探讨肌肉动态等速肌力的性别差异以及动态和静态肌力的相关性。研究结果表明 :动态肌力的性别差异与其表示方法有关 ;女生肌肉的作功功率不及男生 ,但是肌肉耐力与男生没有差别 ;动、静态肌肉力量的性别差异存在着明显的不一致性 ,不能简单地通过静态肌力的检测来评价动态肌肉功能 ;不同性别学生肢体围度大小与肌肉功能水平的关系缺乏严格意义上的一致性     

我国速度滑冰优秀男子运动员膝、踝关节肌力特征的比较研究

通过运用CYBEX NORM多关节等速测力及康复系统对我国男子500m国际级健将和国家级健将速度滑冰运动员下肢膝、踝关节肌力进行测试和分析。结果表明，两组运动员在部分膝、踝关节肌力特征上存在显著性差异，国际级健将运动员表现出较国家级健将运动员更合理的肌力特征。