Holo on the feet. right when the blue one came out I suffered a flare up of plantar faciitis. I taped a blue holo to my heel with a band aid (blue to foot) It took almost a full 24 hours, but there is no pain or swelling. I treated my fascia with massage and now I am back in my usual dance groove. Yes I sleep with the blue holo still - on my cell. Drinking lots of green holo charged beverages too. Taking the metallic taste well