People get athlete’s foot by coming into contact with dermatophytes, a group of fungi that feed on the protein in your outer layer of skin. The most common culprit worldwide is a species called Trichophyton rubrum. These fungi thrive in warm, damp environments, and the infection spreads through both direct skin contact and contaminated surfaces like shower floors, pool decks, and shared personal items.
How the Fungus Reaches Your Skin
Athlete’s foot spreads in two main ways: picking it up from a contaminated surface, or getting it from another person’s belongings. A single infected person can shed fungal spores across a locker room floor, pool deck, or communal shower. When you walk barefoot through those spores, they can penetrate your skin and begin to grow.
The fungi that cause athlete’s foot can survive for several months on warm, humid surfaces like indoor pool areas and public showers. That long survival time is what makes these environments so effective at spreading the infection. Every barefoot visitor who passes through picks up a fresh chance of exposure. The risk is highest in any place where people frequently walk barefoot: hotel rooms, gym locker rooms, fitness studios, and swimming pool changing areas.
Indirect contact matters too. The fungus lives comfortably in socks, shoes, and towels, all of which tend to stay moist. Sharing any of these items with someone who has athlete’s foot is a reliable way to pick up the infection yourself. Even walking barefoot on a dry hotel room carpet carries some risk, because the fungus can remain alive on dry surfaces for a period of time.
Why Your Feet Are the Perfect Target
Your feet spend most of the day sealed inside shoes, creating exactly the conditions these fungi love: warmth, darkness, and moisture. Prolonged use of closed-toe, non-breathable footwear traps sweat against your skin, softening and breaking down the outer layer in a process called maceration. That softened skin is far easier for fungal spores to penetrate. The spaces between your toes are especially vulnerable because moisture collects there and air circulation is minimal.
Historically, athlete’s foot was rare in populations that didn’t wear enclosed shoes. The global spread of the most common fungal species tracks directly with the rise of occlusive footwear, military campaigns that kept soldiers in boots for weeks at a time, and increased international travel. The shoe itself isn’t the cause, but the environment it creates on your foot is what tips the balance in the fungus’s favor.
Who Is Most at Risk
Anyone can get athlete’s foot, but certain factors stack the odds. Hot, humid climates increase your baseline risk. So does heavy sweating. People who exercise frequently, wear work boots for long shifts, or spend time in communal wet areas face more exposure. Men are affected more often than women, though the reason isn’t entirely clear.
Your immune system also plays a role. People with weakened immune function, diabetes, or poor circulation in their feet are more susceptible and may develop more severe forms of the infection. If you’ve had athlete’s foot before, you’re at higher risk of getting it again, partly because old shoes can harbor living fungal spores and reinfect you after treatment.
How Quickly Symptoms Appear
There’s no well-established incubation period for athlete’s foot. Unlike many infections where you can count the days between exposure and symptoms, the timeline here varies widely and hasn’t been pinned down by research. Some people notice itching and peeling within days of a known exposure, while others may carry the fungus for longer before anything becomes visible. The infection typically starts between the third and fourth toes, where moisture is highest, and can spread to the soles and sides of the foot over time.
The classic symptoms are itching, burning, redness, and flaking or peeling skin between the toes. In more chronic cases, the soles of the feet become thick and scaly in a pattern that extends from the bottom of the foot up around the edges, sometimes called a “moccasin” pattern. A more aggressive form can cause blistering and raw, ulcerated skin between the toes that spreads to the top or arch of the foot.
Keeping the Fungus Off Your Feet
Prevention comes down to two things: limiting your exposure and keeping your feet dry. Wear sandals or flip-flops in communal showers, pool areas, locker rooms, and hotel rooms. Never share shoes, socks, or towels with someone who has an active infection.
When you do wear closed shoes, cotton socks help absorb moisture better than synthetic materials. Antifungal foot powders serve double duty: they reduce moisture between your toes and inhibit fungal growth on the skin’s surface. A small study in athletes at high risk for the infection found that daily use of an antifungal spray powder significantly reduced both skin moisture and fungal growth compared to untreated feet, providing indirect evidence that regular use lowers your chances of developing the infection.
Rotate your shoes so each pair has at least a day to dry out between wears. Old shoes that you wore during a previous infection are a common source of reinfection. Either treat them with antifungal powder or replace them entirely. After showering or swimming, dry your feet thoroughly, paying extra attention to the spaces between your toes, before putting on socks or shoes.