Study: Sitting straight is 'bad for backs'

Scottish and Canadian researchers say sitting up straight is not the best position for office workers and is not the best one for backs‘ health.

Scottish and Canadian researchers analyzed various sitting position including the presumed best position “sitting up straight” and wanted to see which position is good for the backs’ health.

They used a new form of magnetic resonance imaging (MRI) to see how each position produces strains in the back. The research was carried out at Woodend Hospital in Aberdeen, Scotland.

Studies were done earlier and it was known that sitting contributed to lower back pain. When one sits for hours the positions adds strains to the back and causes aches and pain.

British Chiropractic Association did a study on office workers and their data showed that nearly 32% of the population spend more than 10 hours a day seated. An improper sitting position at work will lead to chronic back aches and pains.

They found about half of those surveyed did not leave their desks, even to have lunch. Two thirds of them also sit at home when they get home from work. Hence it is imperative to find the best suitable sitting position.

Rishi Loatey of the British Chiropractic Association told BBC:

"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."

My friend once told me that our bodies have been designed for hunting purposes and is meant for moving and active working. Since we get food easy these days we seldom hunt and sit most of the time putting too much pressure on the spine causing back aches.

The researchers for this study showed with the MRI how sitting up straight places an unnecessary strain on one’s back. They told the Radiological Society of North America that the best position to sit on the desk is leaning slightly back at about 135 degrees angle as shown in the picture.

The researchers studied twenty two volunteers with healthy backs and they were scanned using a positional MRI machine, which gives the patients the freedom to move when tested.

In this study, the patients assumed three different sitting positions: a slouching position, in which the body is hunched forward as if they were leaning over a desk or a video game console, an upright 90-degree sitting position; and a "relaxed" position where they leaned back at 135 degrees while their feet remained on the floor.

The researchers then took measurements of spinal angles, spinal disk height and movement across the different positions.

The spinal disk movement occurs when weight bearing strain is placed on the spine, causing the disk to move out of place.

The researchers found there was a pronounced disk movement with a 90 degree upright sitting posture. It was least pronounced with the 135 degree posture, indicating that less strain was placed on the spinal disks, associated muscles and tendons.

The "slouch" position revealed a reduction in spinal disk height, signifying a high rate of wear and tear on the lowest two spinal levels.

The researcher concluded that 135 degree position was the best for backs and recommend others to sit in this position while they work or when they sit at home.

Dr Waseem Bashir of the Department of Radiology and Diagnostic Imaging at the University of Alberta Hospital, Canada, who led the study, told BBC:

"Sitting in a sound anatomic position is essential, since the strain put on the spine and its associated ligaments over time can lead to pain, deformity and chronic illness."

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."

Sitting long hours continuously is not a good idea, frequent breaks eases the back as well as refreshes your mind a lot, even a 5 minute break for every one hour helps. But if you are unable to take breaks, then at least try the 135 degree sitting position.