I kept icing my knees as long as there was some swelling. Also after I had been out walking or exercising. I had more swelling with the first knee so I iced that longer. I had a machine I think I saw mentioned here that you could fill with water and ice and then put the pads around the knee to circulate the cold water. I found it to be not as good an a plain old ice pack and kind of a bother to use so hardley used it.