Blisters & Black Toes, or How I'll Never Get a Pedicure Again

Running can be brutal on your feet. It was quite the shock training for my first half marathon and seeing the state my feet went through. Blisters and black toenails are super common among runners. Its just part of the sport, warrior wounds if you want to think about them that way. Most of the time you can alleviate these issues with proper fitting shoes, but all the pavement pounding or trail trekking will still get you in the end. Have I scared you off yet?

I promise I won't post any pictures of gross feet here. I hate it when I go to a website trying to find a blister cure and see a big picture of an open wound. So don't worry, this post will be free of those disgusting images.


I'm more prone to blisters because of my foot shape. The bone below my big toe (Metatarsal) protrudes out a bit and tends to rub against my shoe. Was I in for it during my first half marathon. I managed to develop MASSIVE blisters on the side of my foot below my big toe. I first developed them from running in the same size shoe I wore in non-running shoes. One of the most important things I learned was to always buy a half size, full size, or even (in my case) a full size and a half larger running shoe to help alleviate the rubbing. (See The Marci Files: Choosing The Right Shoe for more info on purchasing running shoes.)

It was incredibly painful and really slowed me down during my last four miles. All I wanted to do was take my shoes off and run barefoot. Luckily, I've experimented on my feet over the past year and I think I've found the right formula for protecting my feet during those long runs.

Blister Prevention

Nike Elite Cushioned No-Show Tab Running Socks - $16 at

Nike Elite Cushioned No-Show Tab Running Socks - $16 at

I went from wearing a size 7.5 running shoe to wearing a size 9 running shoe (a full size and a half up from my regular shoes) and that has helped alleviate some of the blisters from forming. For a while I was only wearing a size 8.5, but I realized I needed to go a little bigger to get some extra room. I also looked into different kinds of socks and although I still haven't settled on what kind would be best (thicker vs thinner), I do wear a pair of Nike socks with extra cushion around the blister prone area and that tends to help. Just wearing the socks and no other protection is fine for short runs, but if I run over 3 miles I need to add a few more things.

At first I tried using regular band-aids, but my feet would sweat and they would slide off. Then I tried using medical pads and waterproof tape to keep them in place. Again, my feet would sweat and the tape would still slide off. My life saver has been Band-Aid Advanced Healing Blister strips. They have a cushioning gel pad that adds extra comfort to my foot, they are waterproof, and they stay in place when my feet sweat. One thing to note about these is that they stay on for several days. You can try and pull them off, but the adhesive is super strong. If its already covering an existing blister it may rip open that blister while you try and take it off (I know, gross). The best thing to do is just leave it on until it comes off on its own, usually only a few days later. You can shower in them and scrub your feet too and they'll stay on. Here's the full write up on them from

  • Multi day protection.
  • Sterilized for safe use on open blisters.
  • Cushioning gel pad relieves pain while protecting the blister.
  • Waterproof, superior adhesive stays in place for multi-day use.
  • Flexible form conforms to skin for greater fit and comfort.
  • Seals out water, dirt and germs that can cause infection.
  • With Compeed® Moisture Seal™ Technology.
KT Tape snuggly wrapped around my foot.

KT Tape snuggly wrapped around my foot.

My other saving grace has been KT Tape. (I'll write up another post about using KT Tape for its true purpose - providing support and pain relief to muscles, ligaments and tendons.) It is the only adhesive tape I've found that doesn't slip off when my feet start to sweat. I wear it for many purposes, and I almost always put it on my feet before a run. I can either tape it directly on my foot which then relieves the friction caused by running, or I add it over the Band-Aid Advanced Healing Blister strip. The only thing to note is that when I do tape it over the band-aid the band-aid usually gets pulled off when I remove the tape (so be careful if you have an existing blister). I've been wearing KT tape on my feet for over a year now and have eliminated most of the blistering. I still get a little here and there, but I've found the combination of the tape and band-aid takes care of any issues I may have. I honestly don't think I would run anymore if I hadn't found these two products.

Black Toenails

As I am prone to blisters due to the shape of my foot, I am also prone to black toenails, especially on my second toe next to my big toe. Technically, I have what is called Morton's Toe, after Dr. Dudley Morton who was a foot doctor in the 1930s. He authored a number of books discussing some of the issues with this foot shape. Technically, I don't have a long second toe bone - it is the relative length of the Metatarsal foot bones, specifically the relative length difference between the first and second that defines this foot shape.

See how the space between my big toe and second toe is deeper than the other toes? That's the relative length between the first and second toe that makes this 'Morton's Toe'.

See how the space between my big toe and second toe is deeper than the other toes? That's the relative length between the first and second toe that makes this 'Morton's Toe'.

Since that toe is longer, it constantly bumps up against the front of my shoe while running. Having a larger shoe definitely helps, but all that bumping causes trauma to the toe and bleeding underneath the nail, hence turning the toenail black. Its really not a big deal at all, it just doesn't look the prettiest. Unfortunately, there's not much that can be done other than covering it with nail polish (which is what I tend to do). It also goes away when training intensity dies down. Some people never get black toenails (lucky ducks!), but if you do get it - don't worry, that just means you're a runner too!