A common problem with runners, a black toenail can be a sign of a larger problem. Find out how to help prevent this injury. Many runners, especially long distance runners suffer from a discoloration of the toenails. Although you can get a black toenail from a sudden, painful trauma that causes bleeding under the nail, for runners it’s not typically the case. The dark discoloration for runners is a chronic, repetitive trauma to the nail caused by the foot constantly hitting the front of the shoe. Trauma is caused by short shoes, running downhill, or wearing loose shoes. This repeated trauma is typically not felt by the runner, micro trauma causes a light amount of bleeding and minimal pressure buildup, so little or no pain is felt. Most runners only notice that something is wrong with their nails when they notice a discoloration to their nail. This should not be ignored. The nail can gradually thicken, and you can develop more problems. As a runner you want to make sure you have properly fitted shoes, and that the shoes are made to compensate for your natural gait cycle (whether you are a pronator or supinator.) If you live here in Savannah, I highly recommend Fleet Feet, they have an excellent staff that is fully trained to fit you with the right running shoe.  However, a better running shoe may not always solve the problem. If there is pressure and pain under the toenail, see your podiatrist. Drainage from a blackened nail can be a sign of melanoma and should not be ignored. For more information or to make an appointment visit www.atlanticfeet.com and you can also follow me on Twitter @Demon_Cped.