Monday, March 1, 2010

San Francisco Podiatrist Explains Why Athlete's Foot is Common in Bay Area Runners and Cyclists

Athlete's foot is a fungus infection of the skin that often occurs in runners, cyclists and other athletes. It just so happens that the San Francisco Bay Area has a climate that can make it easier for you do develop a case of itching, burning, peeling feet that characterizes the condition.

In order for any fungus to grow best, it needs a habitat that is dark, warm and moist. As it turns out, shoes are perfect for this. You put on your running shoes and head out for a run through Golden Gate Park. Your feet sweat (even if it is fifty degrees), and the heat from your feet turns the shoe into a little incubator for the nasty stuff to grow. If it is like many days in San Francisco, you may even get some rain or light drizzle further soaking your shoes. Then you get home and toss your shoes in the closet until you get ready to go for a run the next day.

The problem is that very few closets have heat or air conditioning vents in them. For this reason, the shoes just won't dry out. They stay damp. And damp running shoes equals fungus.

Cyclists have a similar problem. Head out on the road to Nicassio or anywhere else in Marin county on the weekend and you will see hundreds of cyclist out for a ride. Most of them are wearing shoe covers to help keep their feet warm and dry. But these shoe covers don't breathe very well. As a result, all of that moisture gets trapped inside the cycling shoes. Once the ride is over, many cyclists will toss there shoes in the garage right next to their bike. Sitting in a cool and damp garage keeps the inside of those cycling shoes damp as well.

Sooner or later, the fungal spores in the shoes will cause an athlete's foot infection. Often this is just nothing more than mild peeling of the skin on the bottoms of the feet (see picture above). But some people get severe itching, redness and burning of the feet. Once in a while a secondary infection (caused by bacteria) can start an even bigger problem.

So what to do?

First off, it is very easy to prevent athlete's foot by simply drying your running shoes and cycling shoes out. Bring them inside. I usually leave mine near of a heating vent for a couple of hours after I go running or biking. This ensures that the insides of the shoes will stay dry. Dry shoes don't support fungus very well. If you wear cycling shoe covers, take them off after every bike ride to help them dry out.

If you do get athlete's foot, over-the-counter (OTC) anti-fungal treatment creams will usually cure the problem in about 4 weeks. All you have to do is follow the directions on the tube. Make sure you use the cream for about a week after the problem seems to have gone away. Otherwise you might still have some fungus in the skin that can flare back up in only a couple of weeks after you stop applying the anti-fungal medicine.

Keep in mind that if you get athlete's foot, you will have been shedding fungal spores in your shoes. You need to decontaminate them by spraying lysol in your shoes and letting them dry out thoroughly afterward. If the athlete's foot doesn't improve after you treat it yourself with OTC medications, see the best podiatrist you can find.

Dr. Christopher Segler is a runner and Ironman triathlete who practices Podiatry in San Francisco. He offers house calls to busy athlete's through You can learn more about common causes of foot pain at www., San Francisco's best podiatry treatment information site.


  1. So my friend now wants to become one of the chiropodists in our little town. This may sound silly, but I'm just not sure what they do. Do you know?

  2. So I've been really wanting to find some good chiropodists. Do you know how to find them? I could really use some help, thanks.

  3. It's obvious that a sports podiatrist would know the answer to this question. Weather has a huge impact on my skin, too. Cold, dry weather really affects me. Giving shoes, socks, and feet a chance to air out in humid climates is a good idea. Having beaches nearby, and good sandals, would probably help.