At the first glance and during the first couple of days this really seems to be the case.

This is similar to running a marathon race without being in the right physical shape for such a task — just imagine how you would feel the next day after such a race?!

It is similar with the SpinaliS chair.

The body needs a few days to get used to active sitting, but when it gets used to it, sitting on the SpinaliS chair becomes a real pleasure and even ten or more hours of sitting isn't a problem anymore. But what is most important — after an entire working day our back is not hurting, because now strengthened back muscles have taken over the critical task of supporting the spine.