Blisters on the feet are the most common sports injury and seem inevitable when running ultra long distances. One study in the Journal of Sports Medicine 2004;38:498-501 reported that up to 39% of marathon runners experienced foot blisters while running marathons. Until now, there has been limited success preventing blisters. The successful runners have learned to run with the pain of having blisters. Runners have tried everything to prevent blisters including old favorites such as Vaseline, powders and tape. These may help for a short period of time, but are not effective over long distances and may actually help to cause blisters. While distance running, feet get hot and perspire, causing socks to become wet. Moisture significantly increases friction (stickiness) between socks and skin. The higher the friction, the greater the chance of getting blisters. Higher friction limits skin surface movement, yet still allows inner tissue movement causing a shearing effect. This physically separates the two layers which fill with fluid, forming a blister.