You're slouching at your desk when someone almost scares you off your seat by blaring: 'Sit up straight!' It might be the teacher, your mother or the boss.

But actually, sitting up ramrod straight may be bad for your back, say experts.

Occupational therapist Patrick Ker from the Singapore General Hospital (SGH) says: 'It's impossible to stay in this position for too long. It's too stiff.'

He advises: 'Sit at a more reclined angle slightly beyond 90 degrees, provided your chair has back support.'

However, it appears that most offices are a bit too laidback about their workers' physical needs.

Here's a figure to make them sit up: Seven in 10 adults here suffer from some form of work-related ache or pain, usually from improper posture during computer usage. That's according to a 2004 survey done by SGH.

If that situation continues for a prolonged period, tight and strained muscles, or in more severe cases, degeneration of the bone, may result.

Therapists say they are seeing an increase of such patients every year, even though exact numbers have yet to be compiled. Usual areas of discomfort are the neck, shoulders, back or hands, with neck pain being the most prevalent.

Occupational therapist Chen Hui Wen from Changi General Hospital (CGH) says: 'Sometimes people suffer from headaches and they think it's a migraine, but the cause is actually from strained muscles in the neck or shoulders.'

Civil servant Matt Chong, 40, has been suffering from neck and shoulder pain, as well as occasional backaches for five years, and from migraines for close to a decade.

'I sit in front of the computer for up to 10 hours a day and continue doing so at home for one to two hours at night,' he explains, attributing the pain to his hunched posture and long hours facing the computer. He has visited a physiotherapist and Chinese sinseh, but stopped as the relief was 'only temporary'.

Most patients, though, are women, say therapists. A part-time office worker, Ms X.H. Yang, used to suffer from severe pain in her back and hip. At times it was so bad she couldn't walk. The 27-year-old says: 'It was way too soon for me to be hobbling about like a little old lady.'

The culprit turned out to be a poorly designed office chair which was too deep to give adequate room to lean back. Also, its height could not be adjusted to provide a proper angle for her to type in comfort.

Ms Yang used to resort to using a gym ball for back support, and a wrist brace.

SGH's Mr Ker says: 'These measures are all just relieving symptoms that can still recur.'

Education and awareness of proper ergonomics - a field involving the study of object designs such as chairs and tables to best align with the shape of the human body - are also important, say experts.

For example, laptops should not be used for extended periods without a break, because the screen and keyboard positions are fixed, causing users to bend their necks most of the time. Raising the laptop and using an external keyboard is recommended.

On worker education, senior physiotherapist Lim Hun Teck from Raffles Hospital notes the case of one patient who complained of back and neck pain although she had a high-end ergonomically designed chair. He realised: 'She had been sitting in it for a year without making any adjustments since it was issued to her.'

Experts also say workers should note: Kicking off those shoes and raising one or both legs up on the chair while you work is cosy, but this only adds extra pressure on the spine.

And here's news to tell your boss - CGH's Ms Chen says: 'It's very important for office workers to take breaks in between. Preferably every 20 minutes.'

If you can't spare the time, some simple stretching exercises will also help.

The SS 514 Code Of Practice, published by Spring Singapore in 2005, offers ergonomics tips for companies. These include ideal desk heights of 70cm, and on workstation positioning. But industry insiders say awareness of the code is low.

Chairman of the Ergonomics Society of Singapore, Mr Yogesh Tadwalkar, says interest in the practice here 'is improving', but not at the pace seen in Western countries, which have laws in place to implement their guidelines.

Still, if your printers and file cabinets are not within easy reach from the desk, don't gripe. Your human resource team might actually know something you don't.

According to Mr Tadwalkar, this layout is recommended to get employees out of their seats and stretch once in a while.

tanyihui@sph.com.sg

This story was first published in thesundaytimes on June 15, 2008.