There are many health perks to endurance training for events like marathons, but there are some unfortunate consequences to logging that many miles. You could end up with a subungual hematoma, which is medical speak for bleeding under your toenails. This condition of blood collecting under the nailbed can cause some severe pain, and it will also turn your toenails black – painful and not at all pretty.
You can prevent the dreaded black toenail by making sure your sneakers fit properly. If your shoes don't fit well, your foot may slide forward with each step you take. This sliding action brings your toes in contact with the front of your shoe. This consistent tapping injures your toenail which makes it bleed underneath.
To ensure proper sneaker fit, you should have about a thumbs-width distance between your big toe and the end of the shoe. Your heels shouldn't be sliding up and down either. It is worth it to take a trip to a running store and have the running enthusiasts there help you find a shoe that fits well.
Fit's Tip: When this condition arises, you can still wear your fashionable sandals. Just opt for a dark toe nail polish that will cover up your bruise.