Tips to help you stand up for better health

Sitting for long periods — as many of us with office jobs or inactive lifestyles tend to do — may be a quiet health hazard. Recent science suggests that long periods of sitting disrupts the way our bodies should function. In fact, even spending an hour at the gym doesn't cancel out the negative effects of sitting down for hours every day.

• Many of us have jobs that keep us at a desk.
• We also tend to sit down while relaxing — whether we're watching television, playing video games or chatting with friends in person or online.
• What makes sitting for long periods so hazardous, say researchers, is that while we are sitting we don't even make the normal brief but frequent muscular contractions that occur when standing or walking. These small, intermittent movements may be necessary to keep our bodies in good working order.
• When we are sedentary for too long, certain chemicals in the body that play a part in burning fat stop functioning.
• An enzyme called lipase which, when we are engaged in activity, helps muscles to round up fats circulating in the bloodstream, virtually shuts down when we sit down.
• With nowhere else to go, blood fats either stick in artery linings, causing the buildup of plaque, or are stored as body fat.
• Sitting for long periods also reduces levels of "good" HDL cholesterol by almost one quarter, increasing the risk of heart problems and metabolic diseases such as diabetes.
• This may explain why light activity has been shown to reduce levels of blood sugar.

• By contrast, every two hours we spend standing or even walking around at home reduces our risk of obesity by nine per cent and diabetes by 12 per cent, according to the results of a study out of the Harvard School of Public Health.
• Standing burns an extra 60 calories per hour, compared with sitting. That may not seem like much, but over an eight-hour working day that's 480 calories — or roughly 33 pounds in a 46-week working year.
• If you habitually sit instead of stand, you need to either reduce what you eat by an equivalent amount, or burn off that many more calories through activity.
• One suggested prescription for a healthy lifestyle is to do at least half an hour of brisk walking every day and to limit the time you spend watching television to a maximum of ten hours each week.
• It is as important to decrease sedentary behaviour, especially watching television, as it is to do more physical activity — one possible solution is to have a treadmill in front of the television, so you can exercise while you watch.

• If you are obliged to sit for prolonged periods, try to change position regularly.
• You could also exercise your legs under the desk; stretch your neck, shoulders and arms; wriggle in your chair or clench your buttocks and abdominal muscles — anything that gets parts of your body moving that would otherwise be still.
• Most importantly, you should get up and move around at regular intervals.
• Take a short break every hour, if you can, and do something active — even if it's simply walking to the photocopier, or doing sit-ups or jumping-jacks during commericals while you watch TV.