Q: Why do my feet sometimes become numb at times when I cycle outdoors (road bike)? - J.C., Stamford, CT

A: There are two foot conditions that are common among cyclists. One is numbness; the other is a burning sensation in the sole. I believe that both may have causes related to footwear, pedal-attachment system or foot mechanics.

A shoe which is too tight or breaking down may produce these symptoms, so replacing your shoes may help. This is an expensive solution, but if your shoes are worn out it is an obvious choice. If your shoes are not breaking down but you suspect they are too tight, try riding in a thinner sock to see if that resolves your pain.

Many riders experienced foot numbness in the days when toe clips were commonly used. If you're using toe clips, cinching them may be the culprit. In this case, you may find that switching to a newer clipless system solves the problem. But if you are already using a clipless system, the numbness may be a result of using a small-platform pedal. Going to a wider pedal, such as Look or Time, may then be the answer.

Numbness or burning also may occur if your foot moves a lot, especially by collapsing inward, when applying force to the pedal. This, again, may indicate a need for new, more supportive shoes. If your shoes are sound, the fix may be found in custom footbeds that limit movement and make your foot more efficient. A podiatrist or business that specializes in athletic footwear may be able to help you with this. For example, in Boulder, Colorado, there is a business called Podium Custom Footwear that makes custom footbeds. I've known several riders who have had their foot numbness or burning problems resolved by custom insoles. They also became stronger riders once their foot mechanics were improved.

Since you may be suffering from a combination of these causes, it may take some time and experimentation to arrive at a satisfactory solution. Good luck.

Source: fitlinxx.com