Sitting down for too long 'causes health problems - even if you exercise' (Telegraph)
Recent research suggests that inactivity increases the chances of developing diabetes and heart disease, independently of how often someone works out.
One study found that that the chance of developing metabolic syndrome, a condition which can lead to diabetes, rose by 26 per cent for every extra hour a woman spent watching television, no matter how much exercise she took.
Here is the review and more comment from Yahoo
While health officials have issued guidelines recommending minimum amounts of physical activity, they haven't suggested people try to limit how much time they spend in a seated position.
"After four hours of sitting, the body starts to send harmful signals," Ekblom-Bak said. She explained that genes regulating the amount of glucose and fat in the body start to shut down.
Even for people who exercise, spending long stretches of time sitting at a desk is still harmful. Tim Armstrong, a physical activity expert at the World Health Organization, said people who exercise every day — but still spend a lot of time sitting — might get more benefit if that exercise were spread across the day, rather than in a single bout.
Last year I pointed to a similar study. This was the conclusion:
These data demonstrate a dose-response association between sitting time and mortality from all causes and CVD, independent of leisure time physical activity. In addition to the promotion of moderate-to-vigorous physical activity and a healthy weight, physicians should discourage sitting for extended periods
I don't think it is just the sitting. TV is a problem in itself. Interestingly I have just been reading a book - reviewed here - about television and its dangers. One of the things it notes is the physiological damage TV can do:
Among many physiological systems, Sigman looks closely at the endocrine system and at how television distorts the natural occurrence of dopamine, growth hormone, ghrelin, cortisol, adrenaline, oxytocin, melatonin, leptin and prolactin. He shows how television may stimulate particular hormones which, in turn, cause early onset of puberty.The light, the excitement, the emotions have hormonal effects.
OK some humour, The Youngs Turks have a chat about it:
or in the extreme, sitting is really dangerous.