In reply to Tall Clare:
> Assuming that many of you out there reading this during the day are doing so from a seated position, more than likely in an office... does anyone use one of those ergonomic kneeling chairs? If so, do you use the sort that has what looks like a rocker underneath, or the sort that, from the side, has the two pieces forming an X shape?
> Anyone found them to be better/worse/no different to a normal chair?
I used to use one of the x shaped ones on casters, for a few years. Did not suit me really for many reasons - the angle of the legs (knee pad angle not adjustable), angle of the seat which was not adjustable, pressure on the knees, "effort" getting on and off, inability just to move legs, knees, feet, to keep circulation going, etc., all caused me to give up on it.
I just got a fully adjustable every which way office chair and find it far superior and better support. I got one with arms and that has the advantage in rising and lowering, but the disadvantage of leaning on them causing slight twisting since the arms are the only thing that can't be adjusted for height.
I am sure some folk love them, but not for me. If you could try one before buying you may be able to assess whether it suits you personally. Having bought mine I felt I needed to keep using it for far too long before giving it away!