Changes

Bad running form [[Running Form]] will not only make you slow and cause injury, but it is also a leading cause of blisters. With a good [[Cadence]] and running form[[Running Form]], your feet will land gently and quietly on the ground, producing little shearing force or impact. A slow [[Cadence]] or a poor running form [[Running Form]] will produce a sharp shearing force that will tear at the skin, causing blisters over time. Running downhill can make the shearing forces far worse, and a poor downhill running [[Downhill Running]] style is likely to cause serious blisters. When running downhill, your foot should land softly and the braking force should be even for the time the foot is in contact.

A badly fitting shoe can cause blisters even with good [[Cadence]] and running form[[Running Form]]. When buying shoes[[Shoes]], try them on when your feet are warm, preferably at the end of the day, and with the socks you will run in. You should generally choose your socks, and then buy your shoes [[Shoes]] to fit with those socks. Some socks are available in a variety of thicknesses, so you can tweak the fit with different socks.

Your foot will slide around in a loose shoe and the pressure will tend to be in small areas, focusing the friction and shearing forces in hot spots. One test of shoe fit is to put your shoes [[Shoes]] on, but leave the laces completely loose and see if you can walk around without your heel coming out. A good fit will have the shoe fitting gently against your foot, but without any area of higher pressure or pinching.

Remember that losing or gaining body fat can change the size of your feet. [[Shoes ]] that used to fit you perfectly may not longer fit the same. A more acute problem occurs on longer races when the feet swell up. Having spare shoes [[Shoes]] that are slightly larger, or thinner socks for later in a race can help with this problem. Of course, getting the fit right is hard, as you can't practice this until your feet are swollen, and different situations may produce differing levels of swelling.

An inflexible shoe will tend to pull away from your heal when you’re running, causing problems at the back of your heal. A good running shoe should be flexible and allow you to run with a natural form. I would recommend against trying to fix your running form [[Running Form]] with shoes[[Shoes]], as this approach generally involves attempting to create a compensatory imbalance.

The arch is a naturally strong structure, but arches are damaged by forces pushing up under their middles. This is particularly true of the arches of your feet; they are strongest when there is nothing pushing up under the arch. However, if you've worn shoes [[Shoes]] that push up under the arch for some time, this will weaken the arch. This is similar to having a limb in a cast; the cast supports the limb, but the limb weakens quickly. Therefore when you try to move to a shoe without arch support, it can be like taking a cast off a limb. Your foot will take time to strengthen and recover from using arch support. The other downside to arch support is the pressure can easily cause blisters. This is especially true of orthotics.

Ideally, the toe box of your shoes [[Shoes]] should be big enough that your toes can’t touch the sides or top of the shoe. If the toe box is slightly too small, it is easy to cut away the material to prevent contact. I generally leave a bridge of material from the very front of the shoe to near the laces to keep the sole from flopping around too much and just cut away the sides of the toe box.

Even the best socks will not prevent blisters if you have bad running form [[Running Form]] or bad shoes[[Shoes]]. However, a bad sock will cause blisters on its own; it’s vital to avoid cotton socks, or cheap socks not made for running. If you are on a tight budget, try to get a sock with seamless construction and good wicking (moisture transport) properties such as Coolmax. See [[Blister Prevention and Socks]] for more details.

Dehydration can be a contributor to blisters, as the skin loses some of its tension ([http://www.nlm.nih.gov/medlineplus/ency/imagepages/17223.htm skin turgor]) with significant dehydration. However, reduction in skin turgor is generally associated with 6-9% dehydration (excluding glycogen [[Glycogen]] depletion water losses), at which point the dehydration itself should be more of a problem than the blisters. [[Hyponatremia]] is a dangerous condition and one of the symptoms is swelling of the hands and feet, which can cause black toenails or blisters. Read up on [[Practical Hydration]] and [[Hydration 101]].

[http://en.wikipedia.org/wiki/Callus Calluses] are a sign of poor fitting shoes[[Shoes]]. A callus is a spot that is likely to turn into a blister with longer distances. You can file down a callus and keep is moisturized, but that is a symptomatic approach. The key is to fix the underlying problem, which is normally the fit of your shoes[[Shoes]]. Note that a callus is a spot that is thickening; the general thickening of the skin due to being barefoot does not tend to cause this problem. The key is to watch out for small areas or spots that have excessively thick skin.

Like the other desperate measures, taping [[Taping]] can reduce the friction between your sock and your feet. Unlike lubricants and powders, taping [[Taping]] can help absorb some of the shearing force, though this depends on the particular tape used. A flexible tape will just transmit the shearing force to your skin, but an inflexible tape can absorb and spread the shearing force. There are several downsides to taping[[Taping]]

* Buy shoes [[Shoes]] with a wider toe box so that your toes are not pushed together.

* Have someone check your running form [[Running Form]] to make sure your feet are landing softly with the correct paw-back. Listen to the sound your feet make when they land for a scraping sound as well as the sensation of your foot pushing forward in your shoe at the point of landing. This is a sign that you are not pawing-back. * If the problem is occurring on hilly courses, make sure your downhill running [[Downhill Running]] form is right. Your foot should land and be in firm contact before your foot starts to act as a brake. * Check your shoes [[Shoes]] are tied correctly and that the pressure on your feet to slide forward is taken by the area under the laces rather than allowing your feet to slide forward and your toes to hit the end. * Check your shoes [[Shoes]] are not creasing at the toe box and pressing against the tips of your toes. * Buy shoes [[Shoes]] with a longer toe box so that your toes do not reach the end.

* Have someone check your running form [[Running Form]] to make sure your feet are landing softly with the correct paw-back. Listen to the sound your feet make when they land for a scraping sound as well as the sensation of your foot pushing forward in your shoe at the point of landing. This is a sign that you are not pawing-back. * If the problem is occurring on hilly courses, make sure your downhill running [[Downhill Running]] form is right. Your foot should land and be in firm contact before your foot starts to act as a brake.

* Check your shoes [[Shoes]] are tied correctly and that on downhill sections any pressure on your feet to slide forward it taken by the area under the laces rather than allowing your feet to slide forward and your toes to hit the end. * Buy shoes [[Shoes]] with a longer toe box so that your toes do not reach the end.

* Don’t have shoes [[Shoes]] with arch support!

* Have someone check your running form [[Running Form]] to make sure your feet are landing softly with the correct paw-back. Listen to the sound your feet make when they land for a scraping sound as well as the sensation of your foot pushing forward in your shoe at the point of landing. This is a sign that you are not pawing-back. * If the problem is occurring on hilly courses, make sure your downhill running [[Downhill Running]] form is right. Your foot should land and be in firm contact before your foot starts to act as a brake.

* Have someone check your running form [[Running Form]] to make sure you are not heel striking. * If the problem is occurring on hilly courses, make sure your downhill running [[Downhill Running]] form is right. You are more likely to [[Foot Strike| heel strike]] on a steep downhill than on the flat.

* Check your shoes [[Shoes]] are the right size; a loose shoe can rub on the sides of your feet. Also, a shoe that is tight in the forefoot but loose elsewhere can cause excess pressure. * If the problem is occurring on hilly courses, make sure your downhill running [[Downhill Running]] form is right. Your foot should land and be in firm contact before your foot starts to act as a brake. * Check your shoes [[Shoes]] are tied correctly and that on downhill sections any pressure on your feet to slide forward it taken by the area under the laces rather than allowing your feet to slide forward and cause the sides of the forefoot to rub.

* Consider modifying your shoes [[Shoes]] to cut open the area that rubs.

* Check your shoes [[Shoes]] are the right size; a loose shoe can rub on the back of your heel.

* Make sure your shoes [[Shoes]] are not inflexible. As your foot bends when you run, an inflexible shoe will try to slide down your heel, causing blisters.