These are not my words but I found this explanation on a web-site. I in no way can deny or confirm it.
"According to the American Cancer Society (ACS) magnetic therapy is used to reduce pain and treat ailments in various parts of the body. Promoters say magnetic rings, bracelets and other magnetic apparatus work because certain cells and tissues in the body emit electromagnetic impulses. The theory is that when disease or injury hampers the flow of these fields, magnetic energy can rectify the imbalance and reestablish health. Magnetic bracelets and magnetic therapy in general have been marketed as having the ability to alleviate migraine headaches, repair broken bones, improve circulation.........."
Again, I have no clue if it true or not but either way its still a really good looking, classy watch.