Manual material handling performance and fatigue

申请者研究计划的长期目标是了解疲劳对男性和女性工作任务的神经肌肉控制模式的影响，以指导最佳工作实践(即工作：休息指南)、工作效率(即任务组织)和工人安全。 人工搬运(MMH)，如提举，是复杂的人体运动，需要在上肢和下肢的神经肌肉系统中组织多个自由度。运动模式是个体肌肉和神经通路共同工作的结果，以达到满足系统限制的功能结果。有人认为，不能协同协调神经肌肉系统中存在的许多自由度是病理性运动模式的一个标志。在几乎相同的静脉中，神经肌肉协调可能会由于神经肌肉疲劳而受到影响，从而导致完成任务所需的运动模式的改变。此前，NSERC资助的研究开始了解当受到与长时间举起、背部疲劳或手臂疲劳相关的疲劳时，运动学、运动学和神经肌肉适应。利用主成分分析方法评估提升波形和关节相对相位分析，实现了对关节运动协调的适应。在长时间的举重活动中，通过对疲劳肌肉和新鲜肌肉的神经肌肉分析，进一步加强了对运动调节的理解。 到目前为止，研究已经在孤立的情况下调查了不同的举重活动的影响，在那里举重只被认为是主要的工作任务。在许多工作环境中，工人需要长时间坐着，然后在到达预定目的地后抬起重物(EMS、消防、警察、运输/卡车司机)。 五年资助周期旨在加强当前研究项目的工作，并有三个主要研究目标。第一种方法是使用PCA建模方法来区分男性和女性在绝对负荷的整个举重周期中的运动学(节段性运动)、运动性(肩部、胸椎和腰椎关节负荷)和协调性(肩部和背部肌肉模式的肌电监测)的运动轮廓。这将更好地告知工作场所在疲惫状态下与性别差异相关的挑战。第二个目标是确定抬起前与长时间坐着有关的抬起调节、疲劳和组织僵硬。第三个目标是探索使用皮肤骨骼作为一种手段，以减轻在长时间的举重活动中的疲劳影响。

The long term objective of the applicant's research program is to understand fatigue-related influences on neuromuscular control patterns of work tasks in men and women in order to guide best work practices (i.e., work:rest guidelines), work productivity (i.e., task organization) and worker safety. Manual material handling (MMH) such as lifting are complex human movements requiring the organization of multiple degrees of freedom in the neuromuscular system of the upper and lower extremities. Movement patterns are the result of individual muscles and neuropathways working collectively to achieve a functional outcome to meet system constraints. It has been suggested that the inability to synergistically orchestrate the many degrees of freedom present in the neuromuscular system is a hallmark of pathological movement patterns. In much the same vein, neuromuscular coordination may be compromised due to neuromuscular fatigue resulting in modification of movement patterns required to complete the task. Previously NSERC funded research began to develop an understanding of the kinematic, kinetic and neuromuscular adaptations made when challenged by fatigue either associated with prolonged lifting, back fatigue or arm fatigue. Using a principle component analysis approach to assess lifting waveforms and relative joint phase analyses, accommodations to the coordination of joint movements were realized. The understanding of the movement accommodations were further strengthened through neuromuscular analysis between tired and fresh' muscles during the prolonged lifting activities. To date, research has investigated the impact of different lifting activities in isolation where lifting only is considered the major work task. In many work environments require workers to sit for a long period of time and then lift heavy loads upon arriving at the intended destination (EMS, fire, police, transportation/truck drivers). The five-year granting cycle intends to build off the work of the current research projects and has three major research objectives. The first is to use the PCA modeling approach to discriminate the kinematic (segment motions); kinetic (shoulder, thoracic and lumbar spine joint loading); and coordination (electromyographic monitoring of shoulder and back musculature patterns) motion profiles over the entire lifting cycle of absolute loads between men and women. This will better inform the challenges associated in the workplace related to gender differences during fatigued states. The second objective is to determine the lifting accommodations related fatigue and tissue stiffness related to prolonged sitting prior to lifting. The third objective is to explore the use of a dermoskeleton as a means to mitigate the effects of fatigue during prolonged lifting activities.