So if you are reading this at the moment, you will most probably be in front of a computer, on your laptop, iPad or even using your phone….now just spend a minute thinking about your posture: how are you sitting? Is your back straight or twisted to one side? Are you on a chair or slumping on a sofa with the laptop on your lap? How close are you to the screen? Are your hands on a keyboard or a mouse? How comfortable do you feel? You would probably have heard a lot about keeping a ‘good’ posture when using your computer. So what is ‘good’ posture? Well this is the usual advice: The picture below summarises some of the ‘key points of the less straining posture for your back:
- Keep the natural curves of your back, so avoid bending forward too much or ‘slumping’ on your chair. Your lower back should be in contact with the back rest of the chair, and keep your hip and pelvis on a 90-120 degree angle. So yes, it’s better to recline backwards slightly, ‘opening’ your hips.
- Knees should be around 90-100 degrees, making sure you can fit 2/3 fingers between the end of the chair and knees.
- Feet should be on the ground or on a foot rest, but never ‘dangling’.
- Elbows 90-120 degrees.
- Monitor should be arm’s length away.
- Keyboard should be fairly close to you on the table, so you can keep elbows at the right angles. The mouse should be as close to you and at the side
Assessing a work station
Let’s have a look at John’s posture:
- His lower back keeps in contact with the chair. His feet are on a foot rest.
- Elbows, pelvis/hips and knees are all about 90-110 degrees which appear quite comfortable.
- His keyboard is quite close to him, so he does not need to stretch his arms.
- A common mistake is people putting diaries or notepads in front of the computer, so the keyboard ends up too far AWAY. So if you need all that stuff, use a document holder.
What could John do to improve his posture?
- The screen appears too far away. He should be able to touch it with the tip of his fingers.
- Raising the screen may help too. So the top of the monitor it’s in line with his eyesight
SO, IF I MAINTAIN A GOOD POSTURE, WILL MY BACK BE OK?
Bad news, unfortunately, sitting is already quite a ‘straining‘ activity for our backs. In your back you have vertebrae (the bones), and discs (the softer bits in between the vertebras that allow movement in our back and they also work as shock absorbers). Discs change shape to accommodate movement in the spine. The diagram below represents two studies regarding the amount of disc pressure that 3rd/4th lower back disc can have while doing activities ranging from lying on your back to sitting down or lifting a box. So let’s say that standing straight puts 100% pressure in your disc, what is the different changes in pressure if:
- lying on your back: around 25%
- Standing straight: around 100%
- sitting 90 deg hips: 125%
- sitting slumping : 175 %
- sitting 120 deg hips: 50%
- lifting a 20 kg box ‘stooping’: 450%
So, compared with a standing posture, when you are sitting your discs are under an increased strain, and depending on how you sit, you will be putting more or less strain onto your back. It is not only the discs. Somebody who spends too long sitting, in the same posture, has more chance of straining the back postural muscles, and as a result weakening the back.
GOOD POSTURE, IS A VARIABLE ONE!!
Yes all this posture advice that we have given you before, try to follow it… however, prolonged sitting is really the problem. Still, even if you manage to hold this ideal sitting posture for a long time, especially if you are a back sufferer, you will be sore, so the answer is really to keep changing posture, and not to get stuck in the same one for hours: “an ideal sitting posture is a variable one!!!” (McGill 1990)
So this is just ONE possible short-term sitting option (now, this should not become your way of sitting, as you can end up straining your neck, for example)
So, be sensible, but keeping you away from a ‘fixed’ posture may be the key to the problem!
Play with the settings of your chair a few times a day and keep adjusting them so your back is not always ‘locked’ in the same position.
So keep changing your posture, and even better, get out of your chair at regular intervals!
… and what else can I do to reduce back trouble with sitting?
1) GET UP: Well, the first and most important is BREAKS. Get off the chair every half an hour if you can. If you are in a big office, make your default printer far away from your desk, stand up when you talk on the phone, make cups of tea… there is even software to freeze your computer every now and then so you remember to move. 20 seconds out of your chair already appear to make a big change. We can’t really emphasize how important it is to move out of your chair! Every back sufferer could tell you how they find sitting in a chair for too long a strain.
2.1. You can do a few stretches during your day in the office: some gentle arching of your back can take your lower back from that ‘flexed’ position to a more extended one, relieving some of the strains in the muscles
2.2. Stretching your hamstrings can often help to relieve some of the symptoms of back pain. You can stretch your hamstrings as John is doing. Hold the stretch for about 10 seconds with each leg and repeat 2 or 3 times, trying to reach a little further each time!
If after reading his you suspect that working at your desk may be responsible for your back, neck, headaches, shoulder or arm pain, please contact us