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"Why do my legs cramp up during longer bike rides?"

ZocdocAnswersWhy do my legs cramp up during longer bike rides?


I'm a 34 year old athletic male that mountain bikes a couple times a week, 8 months of the year. A few times during longer rides one of my legs cramped up around the knee. The pain was so severe I had to get off the bike and was unable to walk. It took a few minutes, but finally I was able to try to walk it off. I stretched it out and was able to finish the last part of my ride. Wondering if I'm over doing it, or need to perform certain stretches? Also my hydration and potassium intake is very consistent.


Bike riding can be a very healthy and positive way to exercise and have fun. It is important to remember though that during longer bike rides, it can be very easy to become dehydrated, and leg cramps can be a sign of dehydration. Keeping your body well nourished is another means for avoiding painful leg cramps, and so ensuring that you have eaten adequate and healthy snacks at appropriate times during your bike ride are very important. As you mentioned, potassium is important , but there are other vitamins and minerals that you should also consider supplementing in your diet if you do not feel that your intake is adequate. Magnesium is one important mineral that you can supplement in your diet to potentially decrease the risk of having these cramps. Of course, it is best if you are evaluated by your primary care doctor who will be best able to evaluate your medical history, and current presenting symptoms and decide upon the appropriate work up. They may decide to perform some lab tests or imaging studies, and they may recommend you be evaluated by a specialist. Of course, adequate stretching is another way to improve the symptoms you are having as well.

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