According to related research proof: in one's life, standing: 30 years, fall asleep: 23 years, sitting: 17 years and then sit accounted for a large proportion in our life, therefore, a need to accord with human body engineering seating can we sit more comfortable, more healthy life.
The survey suggests that common man-machine seat design requirements are as follows: (
The curvature of the spine healthy right;
Prevent pelvic tilt back;
Tail bone and hip to minimize pressure;
As the pelvis (
Provide effective support,
Reduce pressure and limit the hamstring muscles;
Provide a good support for pelvic and feet.
It is now accepted that need to have a back of a chair, sat up just comfortable.
Of course there is a seat is designed without back of a chair.
Now the one who is, won't again honestly sat in a chair, they can present various postures, back of a chair to give them a chance to rest and relaxation of lumbar, however, to really relax will look at the chair back curve design is reasonable.
Kids like to lai in mother's bosom, or sitting on daddy's lap, these are all natural instinct, parents of children on the body or the feeling of sitting in the lap adjust, make children get the most tender and comfortable arms, gently swaying again, the child soon fell asleep.
Seating is imitation of the warm embrace of life.