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What Causes Black Toenails in Runners?

Published on March 5 Anna

Black toenails in runners are typically caused by repetitive trauma or pressure on the toes during running. This trauma can result from various factors such as ill-fitting shoes, excessive downhill running, or running long distances without proper foot care. When the toes repeatedly strike the front of the shoe or rub against the sock, it can lead to bruising or bleeding underneath the toenail, causing it to turn black. Additionally, running downhill or on uneven terrain can increase the pressure on the toes, exacerbating the risk of developing black toenails. To prevent this condition, runners should ensure they wear properly fitting shoes with ample room in the toe box, trim their toenails regularly, and consider using protective padding or tape on areas prone to friction.