By Anna-Mart Kruger, Physiotherapist, www.physionam.com
Ergonomics is about fitting the task to the person, and fitting the person to the task. When ergonomic principles are applied in a work environment, many workplace injuries are avoided and work performance can be improved. To have “good ergonomics”, ergonomic risk factors with the task and the individual must be identified and eliminated or reduced.
Some common ergonomic risk factors associated with the task include: Awkward postures.
Awkward postures are body positions that are uncomfortable, or put the body parts in use in a mechanical disadvantage. Muscles and joints work most efficiently in specific positions, usually at the mid point of the joint’s range of movement. When muscles are working at the same time as they are being stretched, they are more susceptible to injury.
Positions held for long periods of time can cause fatigue to supporting muscles which results in discomfort and can lead to injury if fatigued muscles are required to work. Certain positions place increased pressure on body structures, and if held for long periods of time can cause damage to those structures. A common example of this is the pressure exerted on discs in the lower back whenever the low back is in a flexed position such as driving or sitting in a chair.
Repetitive movements can lead to overuse of muscles and tendons. Muscles and tendons may be subjected to microtrauma that causes pain. This is especially problematic if the repetitive movements are also performed in an awkward posture. In this case, muscles and tendons may actually rub against other bony structures causing wear or breakdown within the muscles and tendons.
Contact stress occurs when there is pressure exerted on a body part, for example, when kneeling on the floor for an extended period there is contact stress on the knees. Contact stress can cause irritation to the body, particularly when combined with awkward postures. Environmental conditions: Muscles fatigue faster in hot conditions and gripping objects or tools can become difficult to maintain with sweaty palms. Alternating between tasks, or taking more frequent breaks from the task may be required when working in hot weather or confined spaces. In cold conditions, blood flow to the extremities is reduced and consequently muscle performance is reduced. Wearing appropriate clothing and warming up the working muscles with light exercise before commencing the work duties may minimize the impact of cold weather. Loud noise can compromise attention to a task and can create tension within the body. Poor visibility may lead to poor hand-eye co-ordination during a task, or may place the body in an awkward position while straining to see properly.
The blood supply to vibrating areas of the body is reduced, which reduces the ability of the muscles to contract and leads to more rapid fatigue. Whole body vibration is experienced by operators of vehicles, particularly heavy vehicles. Hand-arm vibration occurs in workers using vibrating or impact tools such as rattle guns, drills or hammers.
How to Reduce Ergonomic Risk Associated with the Task. (Heirarchy of Control):
Some common ergonomic risk factors associated with the individual include:
How to Reduce Ergonomic Risk Associated with the Individual.
Maintaining physical health and good posture is essential for preventing injury. A Functional Abilities Evaluation (FAE) can assess an individual’s fitness to perform tasks associated with a job.
How YOUR Physiotherapy can help:
Physiotherapy can help reduce your ergonomic risk factors by analyzing the postures and movements that you use during your work activities, as well as analyzing your body and it’s ability to perform the tasks. Physiotherapists can conduct a Functional Abilities Evaluation (FAE) to assess your physical ability to meet the demands of your job. We may identify risks within your job such as awkward postures and make suggestions for improvement. We may discuss your typical work day with you and provide guidance for avoiding injury or to assist in the recovery of an existing injury. We may suggest you plan your work day to break up prolonged positions with other tasks. We may design a program of stretches that you can do at your workplace to reduce muscle tension created by work activities.