I have recently discovered Citi bikes here in NYC! By far it is the quickest way to get from my daughter’s school to the office at the end of our normally harried morning routine.
Although my ride is only 16 blocks I occasionally get some mild numbness in my index and middle fingers (aka. carpal tunnel syndrome symptoms). But what about long distance cycling?
A friend and colleague Dr. Marty Boyer at Washington University School of Medicine in St. Louis looked exactly at that. He and his group examined 25 road or mountain bike cyclists of varying levels of expertise before and after a 600-km intense 4 day ride.
What they found was interesting. Most (92%) of the patients had either changes in sensation (feeling), changes in muscle strength or both. These changes were not in the carpal tunnel nerve (the median nerve of the wrist) but in the ulnar nerve, the other main nerve that supplies the sensation to the ring and small fingers and muscle innervation of most of the small muscles of the hand.
A high proportion of mountain bike riders experienced sensory changes but surprisingly the level of cycling experience did not correlate with the presence of nerve dysfunction. Type of handlebar, mountain bike vs road bike, did affect the degree of motor nerve dysfunction, but most cyclists had some degree of dysfunction whether it be in lack of sensation or weakness.
Take home messages? Several common sense rules follow. Wear well padded cycling gloves, take breaks and vary hand position while riding and make sure your seat is adjusted properly (a mal positioned seat requires more hand pressure and may affect nerve function).
So although not likely a factor for most of us using Citi bikes for commuting, following some simple rules may be helpful in keeping our long distance cyclists out of harms way.