Just because you're tied to a workstation, there's no excuse for letting your fitness slide. Rebecca Armstrong discovers 'deskercise'

Scientists have claimed that it's as risky as smoking, increases obesity, and that it could lead to deep vein thrombosis if you do it for too long. Yet 59 per cent of us do it every day at work. Sitting at a desk, it seems, can be hazardous to your health.

Research carried out by the British Chiropractic Association has found that 32 per cent of us spend 10 hours or more sitting each day and that half of us don't even take a break to leave our desks at lunchtime. The effects of this sedentary way of working are compounded by the fact that many of us head home to sit in front of the television. According to Professor Marc Hamilton of the University of Missouri, desk junkies are risking heart disease, Type-2 diabetes and obesity. "The dire concern for the future may rest with growing numbers of people who are unaware of the dangers of sitting down too much," he says. His studies "demonstrate a significant impact of inactivity on a par with smoking". A study at the Medical Research Institute in Wellington, New Zealand found that in 62 cases of people with DVT, 34 per cent had spent long periods sitting at their desks at work.

Meanwhile, here in the UK, the Health and Safety Executive (HSE) states that back disorders are the most common form of ill health and disorders at work and 75 per cent of sick days are due to stress and back pain, resulting in an estimated 4.9 million working days being lost. For those of us consigned to being stuck in front of a screen all day, these findings may be scary, but they are also unavoidable we're working longer hours than ever and desk jobs have become the norm.

But there are ways of safeguarding yourself against death by desk. As well as taking regular screen breaks, an industry has sprung up around the idea of making the hours spent at the work station as healthy as possible. And the very latest innovation for workaholics in need of a workout is the GZ PC-Sport & Power Stepper. The device, which costs 99.90 and fits under a desk, looks like a regular stepper, but it actually plugs into your PC. If you stop stepping, your mouse or keyboard will stop working.

The inventor of the Power Stepper claims that it can help you burn up to 400 calories an hour, improving general fitness and muscle tone as well as reducing the risk of DVT. But surely that would give lazy office workers an excuse to stop stepping and take a break from their labours? Apparently not, says Richard Coshott, the director of Gamercize, the company behind the gadget. "The beauty of this is that the computer helps take the minds of reluctant exercisers off the physical effort, because they can choose an activity they enjoy while stepping whether that is emailing, writing blogs or shopping online."

Keen to avoid DVT and to get a workout while working, I try the GZ PC-Sport & Power Stepper for myself. It's simple to set up just plug one cable into the USB port and connect either the mouse or keyboard to the adapter port. Then I start stepping. The first thing I notice is that stepping while trying to type is similar to attempting to pat my head while rubbing my stomach it takes a bit of thought. My second impression is that the Power Stepper is quite noisy. It is soon drawing the attention of my colleagues, with comments like "that looks like hard work" and "you look stupid". After 10 minutes, I'm beginning to sweat. Then the phone rings and I try to type while talking and stepping, which makes me sound like a heavy breather. I decide to cheat and take notes by hand while having a rest.

Although there are different levels of difficulty depending on your fitness, I'm not convinced by the foot-powered keyboard. Luckily, you can use the stepper without connecting it to a PC it will still note how many steps you've taken and how long your session has been. But I can't help thinking that the easiest way to beat office obesity is to exercise outside of work hours or during lunch time.

Neil Randall, the fitness manager for Virgin Active health clubs, agrees. "The idea of using a stepper at your desk is quite a good one," he says, "but you have to be careful, because if you're not doing the exercise right or you have bad posture then it can cause more problems than it solves." There are simpler ways of working out at work, he says. "If your office has stairs, my advice would be to go up and down them a few times a day running up and down steps is a great way to get the blood flowing through the body. Alternatively, walk to the shops for a bottle of water rather than just getting one from the canteen. Stretches at your desk are also good (see box). It's about making sure you are doing some regular exercise, and if you work all week, it's also important to be creative with your time. A 20-minute workout provided it's the right intensity can be just as beneficial as a longer one."

The Swiss ball is another way to exercise your muscles at work and it's a lot cheaper and quieter than the stepper. Used by Olympic athletes, the New Zealand All Blacks and even the English cricket team, these inflatable balls cost as little as 5 and can be used as a muscle-boosting, posture-improving office chair. Simply inflate the ball using a pump and sit on it it sounds straightforward, but the ball is an unstable surface, so your body has to stabilise your position, which improves core strength. And to stay upright, you have to straighten your spine something that tends not to happen when sitting in the average wheelie chair. Although sitting atop a big blue ball still elicits some glances from colleagues, it isn't as intrusive as the stepper and feels a lot more natural.

To get even more health benefits, though, I need to tackle some other desk exercises. At Birbeck University in London, staff and students are encouraged to do stretching exercises to improve flexibility, decrease stress and increase performance. The university recommends doing three or four exercises once an hour, holding each stretch for a count of six and repeating it six times. First up is the neck stretch. Sitting upright, I have keep my face forward and try to touch my left shoulder with my left ear, hold it, then repeat on the other side. I then stand up, feet apart, with hands on hips in order to do a side twist. I turn round as far as I can to the left, then to the right. On to the shoulder roll, which consists of sitting or standing with good posture, then raising my shoulders and rotating them three times forward, then three times back.

My favourite is the executive stretch either sitting or standing, I place my hands on my lower back and push my hips forward and my shoulders back in order to arch my spine. It's then time for a five-minute walk around the office before settling back in for some actual work. The stretches have definitely made me feel less tense and the walk has been a good way to get away from my screen. The Swiss ball is staying as my chair of choice, but although the desk stepper might have my best interests at heart, the only thing it has really proved any good for is distracting my colleagues and me from doing much work. Exercising "al desco" might be ideal for some people, but I think I'll stick to working in the office and exercising elsewhere.

The dos and don'ts of office fitness

*Do take a break from your desk every 20 minutes

* Do make sure to sit up straight poor posture can lead to back problems, which are the most common cause of sick days in the UK

* Do try using a sloped desk to rectify poor posture

* Do seek advice from your employers if you are suffering from discomfort at your desk. They should provide you with information on how to work correctly and may be able to provide office equipment to help

* Don't email your colleagues go and talk to them instead

* Don't stay at your desk during your lunch break even a five-minute walk can be beneficial

* Don't spend all day and all evening sitting in front of a screen. Go for a walk, join the gym or, if you must watch TV, try doing some exercise at the same time

The best desk stretches

Neck stretch

Sit tall. Keep face forward, try to touch your left shoulder with your left ear. Hold. Return head upright. Repeat on the right. Do not tense or hunch the shoulders

Side twist

Stand up, feet apart, hands on hips. Gently twist, as far as is comfortable, to the right. Relax. Repeat on the left.

Executive stretch

Sit (or stand) with good posture. Place your hands in your lower back. Push your hips forward and your shoulders back to arch your spine. Relax.

Arm stretch

Straighten your arms out. Stretch your wrists back. Touch your shoulders and repeat.