2. Black and bruised toenails

Description: Blackened and bruised toenails are caused by a repeated impact against the toes or too tight running shoes. Generally, such damage to the toenails occurs during long runs or runs where there is a large proportion of downhill running – which can make the toes hit the inside of the front of the shoe.

Treatment: Rest from running until the discomfort subsides. Also, check your shoes, as these may be too tight in the toe box region.

Training and racing: Once the pain has gone, you can continue training and racing as before. Your black nails may remain long after any pain has dissipated while a new nail slowly grows underneath the damaged one.