It's not called athlete's foot for nothing. It really is a common problem for those who work out. Athlete's foot is a fungal infection of the toes and other parts of the feet. A shower or locker-room floor is a perfect place for the fungus to lurk and spread. The infection can be itchy and annoying. It can also be hard to get rid of and easy to pick up again. Some people, such as those with naturally sweaty feet, are more susceptible.
To avoid athlete's foot, make it a rule to wear flip-flops or shower shoes into the shower and locker room. Take them off to soap your feet thoroughly and replace them before you leave. Make sure you dry your feet well, especially between toes. Put on clean socks when you're done.
Athlete's foot is not a serious ailment. You only need to see a doctor if it persists or affects your toenails. Take it more seriously if you suffer from diabetes or from a weakened immune system due to HIV infection or chemotherapy [source: Consumer Reports].