It will not affect the lumbar spine? not good.

exercise is good, but the score of the time.

First, you ask yourself, why, when working with a yoga ball instead of a chair? To exercise while working? In order to maintain a good posture is going to work? In other words, this child is doing in order to work or exercise?

If it is for work, long muscles tense state, is unable to concentrate on high-intensity work, not to mention, in the course of implementation, if you can not concentrate on the body, there is great risk of dumping injured.

I am very opposed to the now popular multi-thread management, only a few people have the ability to do two things at the same time, I'll wait for a man can do pretty good. If desired, one every two days out while exercising, this is more preferable.

with yoga ball instead of the chair, I do not see any benefit, only risk. Suddenly fall injuries, bad posture or long-term damage to bones and muscles.
doing so, it will only work is not done, the body also collapsed. Or with a normal chair it.

stay healthy is not a difficult thing, but not brain-hole wide open.