Do you want to live longer and be healthier?
Then sit less than 3 hours a day – and when you do sit – sit with better posture.
Recent research shows that sitting for long periods of time is unhealthy and that sitting for fewer than 3 hours a day may add up to 2 years to your life.
A wave of new research indicates that sitting all day is actively damaging your health. By forcing a body designed for movement to hold a crushingly immobile position, sitting strains muscles, slows your metabolism, increases your risk of heart disease, and even shortens your life span. "Sitting is a health hazard on the order of smoking," says Marc Hamilton, PhD, a microbiologist at the Pennington Biomedical Research Center.
Wow!
From about the 1st grade on most US schools have kids sitting hours and hours a 
day. And often physical education or even outdoor recess time are among the first "extras" to go when budgets are tight.
[Or when we teach to the tests.]
Sitting badly
Sitting itself is a problem as our metabolism slows to a halt when we sit – and then most of us sit in bad positions posture-wise when we do sit.
Add to this that we sit more than 3 hours a day makes this sitting-issue a double-plus whammy.
Get out of your chair and move around! work while standing and when you sit:
Here is a better way to sit
