不同肘部支撑高度对打字时相关肌肉活动及舒适性的影响  

The effects of elbow support on muscle activity and comfort while typing

作　　者：杨锆[1] 胡海华[1] 刘加海[1] 陈岚岚[2] 

机构地区：[1]浙江大学城市学院,310028 [2]杭州师范大学钱江学院

出　　处：《中华物理医学与康复杂志》2013年第11期879-882,共4页Chinese Journal of Physical Medicine and Rehabilitation

摘　　要：目的探讨肘部支撑高度对打字时相关肌肉活动及主观舒适性的影响。方法选取10名在校大学生为受试者，分别在离桌面3cm、0cm、-3cm、-6cm及无支撑5种高度下进行打字，利用双极肌电记录系统采集受试者右侧头夹肌、斜方肌、肱二头肌、桡侧伸肌、指屈肌、桡侧屈肌及指伸肌的平均肌电值（AEMG），采用问卷调查对受试者颈部、肩部、手前臂及手部在不同支撑高度下的主观舒适性进行评判。结果肘部支撑高度对斜方肌（F=10．245，P=0．000）、桡侧腕长伸肌（F=6．693，P=0．000）、指伸肌（F=3．580，P=0．013）的标准化AEMG值有显著影响（P〈0．05）。斜方肌在无肘部支撑和支撑高度为3cm时的标准化AEMG值较高，分别为[（174．14±77．50）％]和[（131．02±35．30）％]，肘部支撑高度为-6cm时的标准化AEMG值[（65．00±24．26）％]较小；桡侧腕长伸肌在肘部支撑高度为-6cm和-3cm时，肌肉标准化AEMG值较小，3cm时[（107．91±13．28）％]较高；指伸肌在无肘部支撑和-6cm高度下的标准化AEMG值分别为[（88．774-14．94）％]和[（91．56±9．88）％]，3cm时[（103．09±7．88）％]较高。在不同肘部支撑高度下，受试者同一部位的主观舒适度之间比较，差异均无统计学意义（P〉0．05）。结论肘部支撑高度可改变打字时相关肌肉的AEMG，但对受试者主观舒适性无显著影响，其原因可能与打字姿势和神经肌肉运动控制模式发生改变有关。Objective To observe the effect of elbow support on muscle activity and subjective feelings of comfort during typing. Methods Ten college students voluntarily participated in this experiment. They typed the same text using elbow supports of five different heights. The distance between their elbows and the desk was supported at 3 cm below, 0 cm, and -3 cm and -6 cm above the desk. There was also an unsupported condition. Myoelectric readings were recorded from the right splenius, trapezius, biceps, extensor carpi radialis, flexor digitorum superficia lis, flexor carpi radialis, and extensor digitorum muscles. Perceptions of comfort of the neck, shoulder, hand and forearm, and hand using the different supports were surveyed using a questionnaire. Results One way ANOVA shows that the height of the elbow significantly affects the activity of the trapezius, the extensor carpi radialis and the extensor digitorum muscles. Trapezius muscle activity was higher with 3 cm high elbow support than without support, and the value was smaller when using - 6 em elbow support. The activity of the carpi radialis ]ongus extensor was least when using - 6 em and - 3 cm elbow support, and greatest with 3 em support. Extensor digitorum activity was least when using - 3 em high elbow support and again greatest with 3 em support. The different elbow support heights had no significant relationship with comfort perceptions for any body part. Conclusion The height of elbow support can change the average myoelectrie signals from muscles during typing, but there is no significant difference in the typist＇s perception of comfort. This could be due to a change of typing position and neuromuscular motion control mode in response to the height of elbow support.

关 键 词：肘部支撑 打字 肌肉活动 舒适性 

分 类 号：R49[医药卫生—康复医学]