For as long as I can remember, people have said that you should sit up straight to avoid getting a bad back. However, I have always found sitting slightly reclined to be more comfortable, and in my 11 years of office work, the only time I have ever had a bad back was after performing some clean and presses (a weight training exercise) without warming up thoroughly.
Recent research at the Woodend Hospital in Aberdeen, Scotland, has now shown that a reclined position is in fact better for you than sitting up straight. Sitting up straight is actually more likely to lead to back problems.
According to the British Chiropractic Association 32% of the population spends more than 10 hours a day seated. This is the combined time of sitting while commuting to work, sitting down at work, then sitting again once home to eat and watch television. 50% of office workers do not leave their desks all day, not even to eat lunch.
Researchers used a new form of magnetic resonance imaging (MRI) to show that sitting up straight places an unnecessary strain on your back. They told the Radiological Society of North America that the best position in which to sit at your desk is leaning slightly back, at about 135 degrees.
The researches studied a group of people with healthy backs, split them into three groups – one group slouched forward, the other sat up straight, and the third reclined.
The researchers then took measurements of spinal angles and spinal disk height and movement across the different positions. Spinal disk movement occurs when weight-bearing strain is placed on the spine, causing the disk to move out of place – such injuries are not uncommon in weight lifters.
Disk movement was found to be most pronounced with a 90-degree upright sitting posture. It was least pronounced with the 135-degree posture, suggesting less strain is placed on the spinal disks and associated muscles and tendons in a more relaxed sitting position. The “slouch” position revealed a reduction in spinal disk height, signifying a high rate of wear and tear on the lowest two spinal levels. When they looked at all test results, the researchers said the 135-degree position was the best for backs, and say this is how people should sit.
So slouching foward is still not good for you, but sitting back is!
Rishi Loatey of the British Chiropractic Association said: “One in three people suffer from lower back pain and to sit for long periods of time certainly contributes to this, as our bodies are not designed to be so sedentary.”
Levent Caglar from the charity BackCare, added: “In general, opening up the angle between the trunk and the thighs in a seated posture is a good idea and it will improve the shape of the spine, making it more like the natural S-shape in a standing posture. As to what is the best angle between thigh and torso when seated, reclining at 135 degrees can make sitting more difficult as there is a tendency to slide off the seat: 120 degrees or less may be better.”
So, slouching back is good, forwards not, and sitting upright will damage your spine. So next time you feel a little back pain at work, recline your chair a little. If you boss says anything, remind him of the huge number of working days lost due to back pain each year, and tell him that you are just ensuring that you back stays in good shape.
Sitting straight ‘bad for backs’ – BBC Health News, Tuesday, 28 November 2006.