You're cycling along and you notice your toes start to feel numb. There could be a few reasons for this feeling, ranging from ill-fitting shoes or pedal clips to a potentially serious condition known as neuropathy. If you experience numb toes while cycling, pay attention to what may have precipitated the numb feelings and how long they typically last. Also pay attention to how well your shoes fit and if there could be a problem with your feet not getting sufficient circulation during your ride.
The Wrong Shoes
A casual bike ride around your neighborhood may not demand special shoes, but longer rides require the right shoes for your feet to hold up under the pressure of more intense cycling. Flexible running shoes may not work well because they allow the foot to "collapse" while pedaling and leave your feet feeling numb or sore. Instead, you should buy and use specific cycling shoes to reduce the risk of foot-related problems while riding. Be aware, also, that long rides can widen your feet slightly, so shoes need to account for a little widening.
If you experience repeated episodes of numbness in your toes or any of your extremities, describe to your doctor what seems to trigger the episodes, how long they usually last, how you resolve them and what, if any, other symptoms such as a pain or weakness occur along with the numbness. Pressure on the nerves in the foot can be a common cause of peripheral neuropathy, a condition marked by nerve damage and feelings of numbness or pain in the extremities.
Because a common source of numbness in the ball of the foot is pressure on the nerves between the second and third toes and/or the third and fourth toes, loosening your toe straps or even just the shoe laces can help relieve that pressure. Clipless pedals may also help, along with specially made orthotics to help shift pressure off the ball of the foot. A visit with a podiatrist, especially one who specializes in sports medicine, should help get you closer to a solution.
Weather and Position
Cold weather and wind can also cause numbness in your feet while you cycle. Wearing a pair of overshoes will help protect against cold weather. But if you experience numbness in warm weather, too, it's probably related to nerves or circulation. Try adjusting your seat, keeping your feet more level as you pedal and other tweaks to see if a small adjustment in the position of your legs and feet solves the problem. Talk with experienced cyclists, too, to see if they can spot any flaws in your cycling form.