workplace posture and ergonomics

posture and ergonomics for workstations and computers, for back-pain remedy and repetitive strain injury (RSI) and workplace stress reduction

Employers have a duty to provide safe working conditions and stress-free work environment for all staff, which includes the provision of information and training for employees about workplace posture and ergonomics. Poor posture at work is a major cause of back pain, workplace stress, repetitive strain injury, resulting in lost time, reduced productivity, poor employee health, low morale, and higher costs. This free theory article is provided by Hugh Babington Smith of the UK Etcom Postural Ergonomics Ltd company, and this contribution is gratefully acknowledged. Applying these simple workplace posture and ergonomics techniques and principles will improve the working environment and well-being of staff.

This material initially clarifies and defines what posture is. It also explains the implications of poor posture, why we should improve posture and the techniques for how doing so. Furthermore the article explains in detail why the employer should take an interest in posture.

UK Government statistics do not show the effects of poor posture in the workplace - the Health and Safety Executive reports instead on absence generally through work-related injury, which includes posture-related causes.

Every employee absence is the culmination of a chain of events. For accidents, that chain may be short. For long term effects of poor posture, the chain is invariably longer. The loss to companies is not just the employees who do take time off because of back pain or posture-related repetitive strain injuries, the loss to organizations is also the reduced efficiency, morale and attitude of those who suffer posture-related discomfort or stress and who 'grin and bear it'.

Although we refer in this article largely to work at computer workstations, the principles apply to any work activity and to our whole life - relaxation, hobby, sport, housework, childcare, in fact any activities which involve the use of our bodies.

 

what is posture?

Posture is a static state - 'A position of the body' or 'An attitude' (dictionary.com), 'Posture is arrested movement' (Bobath). By itself it's a word which is often qualified - defensive, poor, bad, aggressive, happy - and is often used in related ways, with overtones of opinion towards something, sometimes with a meaning of falsehood. What distinguishes it from 'position' is the inclusion of a mental ingredient, particularly mood or emotion; ie., posture is a 'position with attitude', so to speak. We always have a posture of some kind or another, even if the mental intention behind it is subconscious. And, of course, it is well documented that body language plays a large part in communication.

Our bones hold us up, our joints link our bones, our muscles move the bones around the joints and our nerves facilitate control of the whole. The key to good posture is correct joint alignment, but muscle activity, balance and nerves are all part of the picture.

 

posture - joint alignment

'Joints' are not just the obvious ones such as those on the arms or legs, but the term applies to any links between bones including the spine, shoulders and hips and weight-bearing joints in the feet. There are about 230 mobile and semi-mobile joints in the body. Our bodies evolved for certain purposes and our joints move in particular ways to fulfill those purposes most efficiently. When alignment is 'correct' - that is, in the evolved position - our body is in balance and our muscles and joints are working with least effort.

This actually applies to movement as well as to static posture. Professional athletes go to great lengths to understand this, for then their bodies are not just in balance but achieving maximum output as well. If our joints are used differently from their 'designed' position, we say they are 'out of alignment'. One of the effects of using joints out of alignment is at least discomfort, which can manifest as pain and eventually become injury.

The degree of mal-alignment is material; a very slight amount and the effect is not immediately serious. A greater degree and we know about it instantly. If a joint is both mal-aligned and under stress, something gives and a break or a tear ensues. 'Something gives' can mean quickly or over a period of time if the stress is lower level but repetitive - hence repetitive strain injury. This can occur anywhere in the body.

Mal-alignment leads to muscle imbalance. Muscles adapt; for instance, an arm in plaster cannot be stretched immediately when the plaster comes off. The same effect happens when a joint is held in the wrong position over a period of time, which is why some people have round backs or slumped shoulders.

 

posture - muscle activity

There are two kinds of muscle in the body, each with their own function. The first kind, postural or 'slow twitch' muscle, is for holding us in the 'correct' position; these muscles are short and in the deepest layers. The other kind, movement or 'fast twitch' muscles, are for moving us, lie over several joints and are closer to the surface than slow twitch muscles. We need both in varying degrees to perform properly.

Even postural muscles will not hold positions for any length of time if they are not used regularly, a good reason in itself for sedentary workers to take exercise and understand alignment. Slow-twitch fibers determine muscle power, whereas quick-twitch fibers determine endurance. The phrase 'muscle tone' in physiotherapy refers to the amount of fibers in the muscle 'firing' at any one time. Even at rest, some fibers are firing and the muscle is 'ready to go'. Only when a body is dead is there no muscle tone. The amount of muscle tone in a posture is largely a function of the amount of support being provided. At an extreme, a person lying on their back has a wide support base, so minimum muscle tone. At the other extreme, a person standing on tiptoes on one leg has a very narrow base and so needs maximum muscle tone in perfect alignment. The muscles are, of course, governed by the brain: lift an empty box that you believe to be full, and it shoots up into the air as your brain orders too many muscle fibers to fire for the task.

 

posture - balance

A contributory factor to holding a posture is balance. Balance can be used in two ways when talking about posture. It can mean the balance of opposing forces ­for instance, are the muscles holding the shoulders back strong enough in comparison with those pulling the shoulders forward? If not, the result is a round back. Secondly, it can mean balance in the sense that if it is not right, the person falls over.

A person with good muscle balance will be able to hold an unstable position for longer because they recruit the postural muscles in the correct alignment and their movement muscles are less involved. A person with poor balance will move a lot and have to use the movement muscles to try to get back to balance. These muscles will get tired quickly and the correct posture will be lost.

 

posture - nerves

We control our movement through our nerves. Messages are passed in both directions between the brain to and from the extremities, the muscles and the joints. If this passage of information is disturbed, we cannot have proper movement. Nerves are physical entities and just as subject to maltreatment as bones and muscle; they can be affected by blows, by stretching, by pressure, by twisting. They pass between muscles, along bones and joints on paths developed, like the rest of the system, during evolution. So again it follows that if alignment is not right, the nerves may be affected.

poor posture effects

What happens if posture is poor? In each of the areas of joints, muscles and nerves there can be effects of mal-alignment. These ill effects may start out as very slight, they may remain at a very low level, but if the cause does not disappear, they will get worse and may become intolerable.

Mal-aligned joints and ligaments may just feel uncomfortable, may ache, or hurt. Shear forces (that is, across rather than along) the spine may affect the discs, putting pressure on the nerves that fan out from the spine.

Muscles will suffer through lack of circulation, which may manifest itself as discomfort, ache or pain as well as lack of performance, getting tired quickly. The body's healing process is impeded when blood-flow is restricted.

Pain may arise when nerves are stretched or inflamed by mal-alignment. Again, the range of symptoms may be from discomfort, through tingling, pins and needles, hot or cold feeling or numbness to pain. A characteristic of nerve damage is that sometimes the symptom is not in the place where the damage is being caused. For instance, a nerve being damaged in the lower back may cause tingling in the thigh or pain around the ankle.

poor posture causes

Why do we have poor posture? There are two sides to this, physical and mental. Physically, the short answer, going right back to fundamentals, is that we are hunter-gatherers, with our roots on the savannah, evolved to spend our days wandering in search of berries or pursuit of prey. We no longer do what we evolved to do. We are emphatically not designed to spend our day sitting on our bottoms staring fixedly at a computer screen or in a car seat staring at the road ahead, or for any of the other activities of our modern life that are so far from our origins.

Mentally, we have unnatural pressures that bear on us all the time. No doubt the link between posture and attitude derives from relationships within our hunter-gatherer community - authority, submission, joy, sadness and so on - but today life is complicated by the sheer variety and duration of circumstances and information that affect us. Thus a person with an oversized mortgage, an unpleasant commute and an unhappy job will tend to have a worn-out demeanor with the posture to show it: round shoulders and a curved spine.

posture discomfort and pain - remedial actions

What can we do to relieve discomfort and pain? There are three main steps:

1                    understand that you can take control

2                    listen to the body

3                    take action

 

1 - take control

Mind and body are closely linked. In many instances we are, without realizing it, in control of the conditions that give rise to pain and are therefore in a position to get rid of it. Once we understand this and consciously take control, we can achieve quite remarkable advances and be very much happier.

It's as much a mental as a physical approach. We know a happy person when we see one - we talk of 'a spring in their step, head up, chest out.' We know instinctively what such a posture means.

Our brain controls our posture through the nerves. Our mind can control our brain One way of implementing that control is to alter our posture positively. Try walking with a spring in your step, add in a little skip, your head up and chest out - you will probably feel a lift and may well have a smile on your face at the same time. That is the first step. Think positively about improving your physical posture.

Very relevant to this is the work by Professor Michael Marmot, Professor of Epidemiology and Public Health at University College, London. He believes that "The reason that low status may translate into poorer health is lack of control and fewer opportunities for full social engagement or participation." (newscientist.com).

There is no reason for anyone to be in 'victim mode', feeling that the world has it in for them, that there is nothing they can do. As many practitioners will tell you, if you cannot bring a person to believe that they can do something for themselves and get them to exercise some initiative, you cannot begin to change their pain. Once they have decided to change, the results can be remarkable.

When people understand why and how to take control, their health improves.

2- listen to the body

The second step is to listen to the body. Why do people 'grin and bear it'? Because they are not listening. Discomfort and pain are telling you something. In particular, with musculo-skeletal matters, the pain and discomfort are telling you that something is not right, something is out of alignment, or something is moving in an incorrect way. Analyze the feeling, look for the root cause and seek ways of changing.

Pain is subjective. There are many cases of people with quite severe injuries that they hardly notice, whilst other people with injuries in the same area but to a lesser degree may be in agony. It is noticeable that when a person is concentrating, they may even temporarily put themselves in the position of not feeling the pain. Indeed, it can take a very long time for the body to 'get through' to the mind and make the point that something is not right. Unfortunately, all this time the damage is getting worse. So it is worth treating the messages of discomfort and pain positively, by listening to them.