Fitness balls 55 cm or 65 cm?

[keeks]

Right after going to the physio for a couple of sessions he suggested getting one of these fitness balls and showed me some exercises to improve "core Fitness" as I mentioned I wanted to improve my long distance cycling. Thing is I went out and got a 55 cm ball and noticed most are 65cm furthermore when I do the exercises I don't exactly feel out of balance etc . Would it be the height of the ball ? I am 5ft 5 "

[Ariadne]

When you sit on the ball, your legs should be at about a 90 degree angle at your knee. It helps to look in a mirror! Does that help?

[mrcharly-YHT]

I would have thought that 55cm would be right for someone who isn't tall.

I've used one of those balls (as a seat). If they are too small, you can just inflate them a bit more.

[keeks]

hi , sorry been a bit busy later to reply. Yes the 90' angle is right so I'll carry on with 55cm