How To Prevent & Treat Black Toenails While Running

running ankle pain

Would you like to learn how to treat and prevent black toenails while running?

Then you have come to the right place.

As a runner, you are no stranger to black toenails—unless you have not been on the running path for that long.

In fact, less than a month ago I did a 12-mile run and forgot to clip my toenails the night before.

Once I got home, took my shoes and socks off and almost freaked out when I saw the blister on the big toe of my left foot.

Black Toenails While Running Explained

Black toenail is a bruise or blood blister under the toenail.

Running with a black toenail isn’t the most enjoyable experience, and if left untreated, the condition can turn into a real nightmare.

Unattended black toenails are not only ugly and painful but can also end up infected—The warm and soggy environment inside of the shoes is the ideal breeding ground for bacteria.

The Good News

Fortunately, black toenails are quite easy to avoid.

In today’s post, I’ll be giving you the lowdown on runners black toenail, how to treat it, and how to prevent the condition in the first place.

Note. Before we go any further, I’d like for the record to explicitly state that I have no experience in the medical field.

The information shared within this post are my own opinions based on my own experience and research.

To err on the side of caution, consult with a certified physician before you attempt any of the advice shared below.

Black Toenails While Running – The Injury Process

Let’s start with identifying the injury process as well as the range of causes of the condition.

This should help you better understand the condition and choose the right course of prevention and treatment.

Running-induced black toenail involves blistering, bruising, or bleeding beneath the nail from continuous trauma, either of the toe cramming into the end of the shoe or the top of the shoe slamming against the nail.

This trauma can force the blood vessels beneath a nail to break, resulting in bleeding beneath the nail that appears black.

Black Toenails While Running – The Causes

A black toenail is caused by wearing trainers that do not have adequate space in the toe-box, forcing the toes to continuously hit against the top, front, and sides of the shoes while running.

What’s more?

Improper shoes are not the only culprit.

The condition can also be caused by wearing the wrong socks, training for long distances at a time, and doing too much downhill running.

Black Toenails While Running

Black Toenails While Running –  The Symptoms

At the onset of the condition, the toenail appears to be of a dark, green or back color that becomes visible under the nail and.

The toenail is also painful when pressure is applied.

The black color of the nail is often the result of the presence of blood due to bruised or broken blood vessels.

For most runners, the big toenail is the most commonly afflicted spot.

How to Treat Black Toenails While Running

In mild cases, a black toenail may not require a doctor’s visit since medical treatment depends on the initial cause.

Following a black toenail injury, it’s best to leave it alone as long as the pain is manageable.

In general, rest the affected toe(s) at least for a couple of days and keep them clean and dry.

If the pain is too much to handle, visit a certified health provider who can puncture the nail to relieve the pressure and drain the fluid.

Also, get your nail checked by a healthcare professional if you notice any notice any redness or infection or when the pain gets worse.

Home Treatment for Black Toenails

If your toe hurts too much, especially 24 hours later, but don’t want to visit a doctor, consider releasing the pressure yourself.

Just keep in mind that it’s always better to have this done by a certified physician.

The Method

First, get your hand on a sterilized paper clip.

Begin by putting it over a flame of a match or light then heating the top until it becomes red hot.

Once the needle is hot, slowly pierce the blister into the thin layer of skin at the edge of the toenail where contact foot pressure will push out any additional fluid.

Next, clean the blister with antiseptic and apply a sterile dressing to minimize infection risk.

How To Prevent Black Toenails While Running

The good news is, preventing black toenails while running is easy.

I mean, really easy.

Here are the measures you should take.

Keep Em Short

As previously stated, the problem behind a black toenail might stem from something as simple as your toenails being too long.

These can indeed wreak havoc on your running feet, whether you’re jogging for a few miles or running marathon.

Not only long toenail can hit the front of your shoe and cause bleeding beneath the nail, but can also cut into the skin of adjacent toes and cause pain and bleeding when running—and you don’t want that.

Make it a rule to ensure that your toenails are trimmed before you run.

This a no-brainer but something most runners scoff at—yours truly included.

To reduce infection risk, trim your nails with properly sanitized nail scissors or clippers, keeping them short and square—not curved—this works because it helps you equally distribute impact on your toes.

Also, you can use a nail file to lightly file sharp edges.

Get the Right Shoes

Since improper footwear is the main cause of the condition, it pays well to invest in a proper pair of trainers.

This is especially the case if you have a lousy history of black toenails while running.

As a rule, go for shoes that are a half size to full size bigger than your regular size.

This way you make sure that you have plenty of room in the toe box.

There should be about a thumb’s length between your longest toe and the end of the shoe.

Just be careful.

You don’t want too much space of course as you don’t want your feet to be gliding and sliding either.

What’s more?

Buy your shoes at the end of the day when the feet are most swollen.

The feet swell to almost a full shoe size over the course of a day.

For more on how to pick proper running shoes, check the following posts:

Post 1

Post 2

Post 3

Avoid Foot Sliding

A useful measure to help stop—or at least limit—the toes from banging into the front of the shoe is by adequately lacing the shoes.

This helps keep the heel in the heel box instead of letting your foot glide forward in the shoe on each foot strike, especially if you’re doing lots of downhill running.

Check this helpful YouTube tutorial that shows you how to lace up your shoes to avoid black toenail.

Another measure to consider, especially if you notice that your feet slide around in your shoes, is to get a rubber or gel insole, which tend to help keep your trainers fit better and help your feet stay in place while running.

The Right Socks

After finding the right shoes for the job, the next step in preventing black toenail is getting a good pair of running socks.

Moisture increases the risk of foot slippage.

As previously stated, that’s what often leads to the injury.

Anything you can do to limit this forward slippage is undoubtedly helpful.

Not only that, activity, heat, and humidity make your feet swell, which forces them to make more contact with the front and the roof of the shoes while pounding the pavement.

That’s why, by the way, black toenails are more common during training in warm weather—when the feet tend to swell.

To sidestep this, wear thin, lightweight, moisture-wicking, temperature regulating socks, which wick away moisture instead of cotton or wool ones.

Also, during the summertime, avoid wearing thick socks.

Instead for, for lighter and thinner material socks that will wick moisture away.

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There you have it.

See, preventing black toenails while running is no rocket science.

All you got to do is to pay a little attention to your feet and running shoes.

Do that, and you should be able to steer clear of most of these painful nuisances with much ease.

Now it’s your turn.

Do you have any time-tested black toenail prevention tips?

I’d love to hear from you in the comments section below.

In the meantime, thank you for reading my post.

Keep Running Strong

David D.


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