One in five office staff has had to take time off work sick in the past year due to back pain, a new report has revealed.
Half of workers have suffered some back discomfort in the last 12 months, with many saying they are in constant pain.
The worst affected are those aged between 55 and 65, according to a study of 1,600 workers, by healthcare charity Nuffield Health.
A third of those surveyed said they had lived with back pain for more than a year.
Cabella Lowe, of Nuffield Health, said: "Back pain is often a combination of factors, which can include poor posture, weak spinal supporting muscles and poor movement patterns.
"People who are inactive for large parts of the day, typically hunched over a computer keyboard, often suffer with back pain."
Back experts say the best way to reduce pressure in the back is to be in a standing position - but clearly this is not always practical.
When sitting, the main part of the body weight is transferred to the seat. Some weight is also transferred to the floor, back rest, and armrests.
Where the weight is transferred is the key to a good seat design, experts say.
A number of leading retailers now design office chairs and furniture to help minimise the risk of back pain and other strain injuries.