Can power plate be painful?

Hi,
Depends what you mean by painful, the general 'ache' from putting muscles under tension is always there (as with any exercise) but if you have some underlying problems, injuries etc they can be the wrong kind of pain.
Power plates are a relatively new technology, so there is an extended health assessment questionaire you will need to fill out before embarking on a program which will hopefully capture any concerns, but to be doubly sure always check with your doctor. Having a qualified professional teach you the basics is also important as well.
My clients find the sensation the strangest part at first but once they are used to it they find them very effective!
Hope this helps,
James