使用不同高度及材料的键盘手托对相关肌肉活动的影响

目的探究打字时使用不同高度与不同材料的键盘手托对相关肌肉活动及主观舒适度的影响。方法选取被试者10名,让其使用不同高度及不同材料的键盘手托打字,分析对指浅屈肌、尺侧腕屈肌和上斜方肌活动及相关部位主观舒适度的影响。结果使用不同高度的键盘手托,对指浅屈肌与尺侧腕屈肌存在显著影响,对上斜方肌无显著影响,对被试者手腕与手部的主观舒适度有影响。使用不同材料的键盘手托,对指浅屈肌有显著影响,对尺侧腕屈肌与上斜方肌无显著影响,对被试者各个部位的主观舒适度无影响。结论使用1.5cm高度的键盘手托可以降低前臂肌肉的负荷,提高手腕与手部的主观舒适度。使用软性材料的键盘手托会使指浅屈肌更为省力,但在主观舒适度方面并无明显变化。

The Effects of Keyboard Holders with Different Heightsand Materials on Muscle Activity

Objective To explore the effects of keyboard holders with different heights and materials on muscle activity and subjective comfort level during typing.Methods 10 students participated in the experiment.The flexor digitorum superficialis, flexor carpi ulnaris and upper trapezius's surface Electromyographic(EMG) signal were recorded while the participants were using different keyboard holders, and the data of surface EMG signal and subjective comfort level were then analyzed.Results One way ANOVA shows that the height of the keyboard holder significantly affected the activity of flexor digitorum superficialis and flexor carpi ulnaris, but had no significant effect on upper trapezius.Besides, it had significant influence on subjective comfort level for wrist and hand.The material of the keyboard holder significantly affected the activity of flexor digitorum superficialis, but had no significant effect on flexor carpi ulnaris and upper trapezius.And it had no significant influence on subjective comfort level for body parts.Conclusion Using the 1.5cm-heigh keyboard holder can reduce discomfort of the forearm muscles and improve the subjective comfort level of the wrist and hand.The soft material keyboard holder can relax the flexor digitorum superficialis, but there is no obvious influence on subjective comfort level.