The term “ergonomics” is derived from two Greek words: “ergon,” meaning work, and “nomoi,” meaning natural laws. Ergonomists study human capabilities in relationship to work demands.
Refers to “the carriage of the body as a whole, the attitude of the body, or the position of the arms and legs”. It is the position in which you hold your body upright against gravity while standing, sitting or lying down. Good posture is the position which is attained when the joints are not bent or twisted and the spine is aligned. Maintaining good posture involves training your body to move and function where the least strain is placed on bones, joints and soft tissues.
In recent years, ergonomists have attempted to define postures which minimize unnecessary static load and reduce the forces acting on the body. All of us could significantly reduce our risk of injury if we could adhere to the following ergonomic principles:
- All work activities should permit the worker to adopt several different, but equally healthy and safe postures.
- Where muscular force has to be exerted it should be done by the largest appropriate muscle groups available.
- Work activities should be performed with the joints at about mid-point of their range of movement. This applies particularly to the head, trunk, and upper limbs.
- Optimize breathing and circulation
- Maintain the bones and joints in the correct alignment so that muscles are being used properly and efficiently
- Help reduce or prevent the abnormal wearing of joint surfaces that could result in degenerative diseases, such as arthritis
- Decrease the stress on the soft tissues, such as ligaments, muscles, tendons and discs
- Prevent the spine from becoming fixed in abnormal positions
- Prevent fatigue because muscles are being used more efficiently, allowing the body to use less energy
- Prevent postural strain or overuse problems
- Prevent neck or back pain
- Prevent muscle fatigue
- Contributes to a healthy image or appearance
Complication of Poor Posture and Ergonomics
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.
How to know if you are sitting correctly:
Complete a posture and ergonomic checklist and see how you “measure up”.
Tips for Improving Good Posture and Ergonomics
- Keep your back straight, maintain all 3 natural curves in your spine
- Distribute your weight evenly on both hips
- Keep your head and neck aligned over your shoulders
- Sit back in your chair; your back should be supported by the seat back
- Adjust your chair height so that your hips are slightly higher than your knees
- Be sure your feet are supported by the floor or a footrest
- Avoid sitting for long periods of time; get up from your chair at least once every hour
- Do not twist or bend your back from a seated position
- Identify the warning signs of back pain caused by poor ergonomics and posture
- Keep the body in alignment while sitting in an office chair and while standing
- Get up and move
- Use posture-friendly props and ergonomic office chairs when sitting
- Increase awareness of posture and ergonomics in everyday settings
- Use exercise to help prevent injury and promote good posture
- Wear supportive footwear when standing
- Remember good posture and ergonomics when in motion
- Create ergonomic physical environments and workspaces, such as sitting in an office chair at a computer
- Avoid overprotecting posture
Basic and important guidelines for office ergonomics:
Adjust the height of your chair so that your feet rest comfortably on the floor and your knees are about level with your hips. If your chair doesn’t offer lumbar support, place a cushion between the curve in your lower back and the back of the chair.
Key object positioning
Keep key objects — such as your telephone, stapler or printed materials — close to your body to prevent excessive stretching. Stand up to reach anything that can’t be comfortably reached while sitting.
Place your mouse within easy reach on the side of your keyboard. Keep your wrist in a natural and comfortable position when you’re using your mouse.
Use a wrist rest to minimize stress on your wrists and prevent awkward wrist positions. While typing, hold your hands and wrists above the wrist rest. During typing breaks, rest the heels or palms of your hands — not your wrists — on the wrist rest.
when you’re typing, keep your wrists in a straight, natural position — not bent up, down or to either side.
If you frequently talk on the phone and type or write at the same time, use a headset rather than cradling the phone between your head and neck. Experiment with various styles until you find the headset that works good for you.
if your chair is too high for you to rest your feet flat on the floor, consider using a footrest. Various types of footrests are available — or get creative and make your own. Try a small stool or a stack of sturdy books.
Center your body in front of your monitor and keyboard. Sit up straight, keeping your thighs horizontal with your knees and at about the same level as your hips. Keep your forearms level or tilted up slightly.
Generally, the desk should be at least 19 inches (48 centimeters) deep, 30 inches (76 centimeters) wide and, depending on your height, up to 34 inches (86 centimeters) high. Under the desk, make sure there’s clearance for your legs, knees and thighs. Don’t use space under the desk for storage.
Place the monitor directly in front of you, about an arm’s length — generally 18 to 28 inches (46 to 71 centimeters) — away. The top of the screen should be slightly below eye level. If glare from fluorescent lighting or sunlight is a problem, turn off some or all of the overhead lights or close the window shades. Place your monitor so that the brightest light source is to the side.
These four reference postures are examples of body posture changes that all provide neutral positioning for the body.
The user’s torso and neck are approximately vertical and in-line, the thighs are approximately horizontal, and the lower legs are vertical
The user’s legs, torso, neck, and head are approximately in-line and vertical. The user may also elevate one foot on a rest while in this posture.
Reclined sitting posture:
The user’s torso and neck are straight and recline between 105 and 120 degrees from the thighs.
A comfortable work space can help you feel your Good at work.