Smarana Puntigam has been running multiday races for over 20 years, including the 3100 mile race eight times. This is the first of a series of articles on dealing with common issues that crop up during multiday races...

How to avoid blisters? - that is a big one for a multiday runner. If you do shorter races, blisters are inconvenient, but easy to deal with because you do not have to run on them the next day. However, once you have blisters in a multiday event they can really influence your performance a great deal. Depending on the area the blisters appear in, and whether they get inflamed, the range of pain goes from hardly-felt to “I think I have to stop, I just can not take the pain.“ So, the best thing is always to prevent blisters in the first place.

Here are the main issues to deal with:

1. Wet feet

One of the most important things is to keep your feet dry - if there is a lot of moisture, the skin gets very sensitive and prone to blisters.

  • powder.jpgPowdering your feet several times a day with foot powder or baby powder can help you to reduce the friction in the shoes and to keep your feet dry. There are also excellent crèmes that keep the feet soft, elastic and reduce also the friction. Vaseline is not so good, because it does not allow the feet to breathe and I always feel that my feet are sliding around too much inside the shoes. However from my experience if the race is longer than a day, powder is the way to go.
  • There are runners whose feet simply sweat more than others, and who will always have wet feet. Many runners cut open their shoes to let the steam and heat out of their shoes.
  • Rain makes the skin on your feet 'crumple' and become much more blister-prone. Our article on rainy weather has a whole section on this... 

2. Choose your socks wisely

  • The big variety of socks is sometimes confusing - there is such a big selection of socks, each promising their own special feature.
  • Don't use cotton socks - they get soaked with sweat and moisture, which does not go away. This was one of my main problems when I started ultra-running and that is why I got a lot of blisters. Dipali Cunningham, one of the leading female multi-day runners, was shocked when she saw me showing up for my first 700 miles race with cotton socks, and gave me valuable information in this regard.
  • Use socks that are not too thick and are made of a fabric that does not store water (i.e. coolmax). For example Nirbhasa Magee, who ran the 3100 Mile race in 2015 and 2017, is very fond of WrightSocks, a thin sock with a double layer - this means the layers of the scok rub against each other rather than the skin. 

3. Ill-fitting and narrow shoes

  • cutaway-shoe.jpg
    Cutting to avoid an upcoming blister on the side of the foot, just below the toe
    Don't take new shoes for marathons or long distances; it takes some time for the shoes to get the right shape for your feet. They have to get used to one another. The shoe size should be at least one number bigger than the size of your foot, with plenty of room in the toebox so your toes don't rub against the front.
  • When you are running ultra distances your feet keep swelling, and you may need extra wide shoes. The first day you can still run in your usual running shoe, but as the race progresses, your feet keep changing. A shoe that perfectly fits on the morning of the third day of a multi-day rice, might not fit any more in the evening.
  • Also you may need a different insole, or to cut the one you have. The insoles that come with the shoes are not flat in the heel area, but have edges that bend upwards. As your foot swells, the heel doesn't fit any more into the area of the insole and the edges of the insole can cut into the heel and sides of the foot, creating blisters.
  • Blisters or potential blisters on the toes or sides of the feet might be alleviated by cutting away the part of the shoe that is rubbing against it, as long as it does not affect the shoe's stability. You will probably need to cut down all the way to where the top of the shoe joins the sole to remove the friction.

4. Hot feet

Where there is friction, there is heat.

  • Some use creams to reduce the friction, but on the long run from my experience powder is the way to go, since it keeps the feet dry and reduces the friction.
  • Again, cutting your shoes reduces heat as well as friction.
  • There are creams that help to cool down your feet. The skin absorbs the cream, so that you can take powder after some time.
  • During breaks, you can put your feet into a plastic bag and put them into ice water to cool them down and reduce the swelling.
  • Changing your socks and shoes frequently will help to air the feet and get rid of moisture and heat. 

5. Taping 'hot spots' and callouses

  • As a runner you most probably know your 'hot spots' - areas of the feet that very easily turn hot or red during a run. If you don't know them yet, check your feet after a longer run and try to locate them. Once you do know them tape them before ultra runs. You can use paper tape or very thin tape, but do not use kinesiology tape - it creates a lot of heat and you will get blisters right there.
  • If there is a callous - very often in the heel section - take it away with simple sand paper or special tools from the drug store. When the feet start to swell during multi-day runs, the normal skin is elastic and can expand, while the callous cannot. Spots like that are predestined for blisters.
Cross-posted from