Saturday, 29th October 2022

Sedentary Behaviour Part 2

Last week I reminded you that we all spend far too much time sitting about – and this is dangerous in its own right. Here’s why:

The harmful effects of too much sitting

The risk of death increases for any sedentary time greater than 7 hours a day. One study of office workers found that those who exercised for one hour per day had a premature mortality of 6.8 per cent compared with those who did less than 5 minutes a day, whose premature mortality was 9.9 per cent. Both total sedentary time per day and length of sedentary bouts are predictors of premature death and the combination of the two triples the risk of premature mortality. This has even received a label – ‘the sedentary death syndrome’. The news is not all bad. Though regular exercise does not eliminate the perils induced by too much TV watching, it does reduce the impact. A meta-analysis involving more than 1 million souls found that you needed to watch television for more than 5 hours per day to reduce the benefits of a regular exercise habit. About an hour’s exercise a day offsets the ill effects of sitting at work for 8 hours.

How harmful?

The more you sit about, the higher your risk of developing cardiovascular disease and diabetes – independent of the amount of exercise you take when not sitting about. The extent of the damage from sedentary behaviour has been quantified by a study conducted in Dallas, Texas, of the coronary calcium scores in heart patients. This score indicates the amount of calcium detectable in coronary arteries and is a good indicator of the presence of coronary narrowing, with its attendant risks of heart attacks and sudden death. For this group of over 2,000 patients, each hour of sedentary time per day on average was associated with a 14 per cent increase in coronary-artery calcification. TV viewing time has also been under the microscope. For every additional hour per day of watching the gogglebox there is an increase in the risk of cardiovascular disease of 3 per cent and an increase in Body Mass Index (BMI) of 0.54. Other conditions that have been shown to be aggravated or even caused by too much sitting about include obesity and some cancers, while the death rate from all causes is increased.

The cost of sedentary behaviour

Sedentary behaviour brings a substantial cost to the national purse. A Belfast study for the year 2016–17 estimated that the cost of sedentary behaviour to the NHS was £700 million per annum, with most of this due to the increased prevalence of cardiovascular disease, type 2 diabetes, colon cancer, lung cancer and cancer of the uterus.

Getting us off our backsides

How best to reduce sedentary behaviour, then? Perhaps surprisingly, fidgeting is very effective. And there is no shortage of ideas given by the authors of the Dallas Heart Study paper: take a walk at lunchtime, pace about when on the phone, take the stairs not the lift, use a pedometer as a prompt to keep moving. Others have suggested using more ‘active travel’, such as cycling to work, getting off the bus a stop or two early, walking rather than driving for short trips, getting up and moving about during TV commercial breaks.

There is a move in some companies to introduce standing workstations in place of the traditional desk and chair. The Stand More At Work (SMArT) intervention is an approach adopted by one NHS trust. However, standing instead of sitting may not be enough – and an active workstation has been invented. The Stir Kinetic MI desk (pictured at the head of this Blog) is a computerised desk which detects when its owner has been sitting for too long and moves up and down a few inches to force them to stand up. It can be programmed to account for the height of the user and the frequency of movement required – at just £2,000 surely a lifesaving snip!

Are you signed up?

If you are a visitor and want to sign up to receive the blog each week, click here:

https://mailchi.mp/e4f0caea4029/exercise-fitness-health-blog

Buy my book!