my mum has jst had ano operation on her knee 2 weeks ago! i would like to no of any exercises that will help strengthing her knees? we bought her a swiss exercise ball but recieved no leaflet or dvd with it to show us wats best to do! my mum has also been diagnosed with FM! so unable to do strenious exercise as it cause severe discomfort and tires her muscles easy! any information you can give will be very appreciated!