Abstract：
Some evidence indicates that lower back muscles located at the non‑dominant side of the body are more fatigue resistant than their opposite counterparts presumably due to preferential use of the dominant hand. The aim of the study was to determine if any distinction exists in the surface electromyographic activity of corresponding contralateral non‑fatigued lumbar multifidus (LM) muscles as a function of hand dominance. The relative to maximum root mean square, the median frequency (MdF) and spike shape parameters were computed from the surface myoelectric signals of ipsilateral and contralateral lumbar multifidus muscle of 46 adult healthy subjects (27 right‑handed, 19 left‑handed) during voluntary contractions evoked by the single arm lifts in prone position. Activation of LM as a contralateral muscle to lifted arm was greater than as ipsilateral muscle, independently of handedness. Regardless if LM performed ipsi‑ or contralateral action to the lifted arm, the mean spike amplitude, slope, number of peaks per spike and spike duration were greater and mean spike frequency as well as MdF were smaller in the muscle of dominant than non‑dominant side. Combined changes of spike shape measures indicate increased recruitment, lower firing rates and higher synchronization of motor units in the LM of dominant side as compared to its counterpart.
摘要：
一些证据表明，位于身体非优势侧的下背部肌肉比相反的肌肉更耐疲劳，这可能是由于优先使用优势手。研究的目的是确定相应的对侧非疲劳腰椎多裂肌（LM）的表面肌电图活动是否存在任何区别，这是手优势的功能。相对于最大均方根，根据46名成年健康受试者的同侧和对侧腰椎多裂肌的表面肌电信号计算中值频率（MdF）和尖峰形状参数（27名右撇子，19左手）在俯卧位单臂抬起引起的自愿收缩过程中。LM作为对侧肌肉对举起臂的激活大于同侧肌肉，独立于手法。无论LM是否对抬起的手臂进行了同侧或对侧动作，平均尖峰振幅，斜坡,优势侧肌肉的每个尖峰和尖峰持续时间的峰值数量更大，平均尖峰频率和MdF较小。穗形测量的综合变化表明招募增加，与其对应物相比，占主导地位的LM中的电动机单元具有较低的点火率和较高的同步性。
