i'm a 22 yr female who has been active her whole life (gymnastics, soccer, pole-vault, cross-country, wrestling, hockey, mtn. biking, skateboarding, snowboarding, in-line, rock-climbing) after graduating college i found a job and use my road bike for my commute to work everyday (10-20mi/day) not much. i'm a terrible procrastinator and i usually end up sprinting the 6 mi across DC to work. anyway, i've noticed a kind of numb sensation under my thighs and especially when i'm seated. some times i feel it in my arms too, though not often. so what's the problem, do i need a new saddle? more rest? more time to get to work? should i stretch? thanks.

Stretching and warming up is essential to any exercise. Try to rest a few days and see the numbness goes away. If it does, you're simply overworking your legs, and your legs will adapt to your riding style after time.

I'm guessing your bike isn't well matched to you. i.e. your seating position, the angle(s) of your body and maybe even the size of your frame.

For a short ride like that, numbness should never be present. When I ride for two hours, well, that's another story, all I can think about is how soon I can get off my bike. I find I HAVE to get off the bike and stretch every half hour or so.

I would have your favorite LBS take a look at your form and see if a minor fitting adjustment will solve your problems. It's very likely that you can be comfortable and not have to replace any part of your bike.

What exactly do you mean when you say, "under my thighs ."?

I think most of us would need a bit better discription of the muscle groups involved to attempt to help you.

Thanks,
Bob

Can you characterize the numbness? Are you loosing all sensation, is it a tingling..? Does sensation return much like after a limb which has 'fallen asleep' gets the circulation back?

Dave

so it's not like an actual numb-ness, my legs just feel super funny, though i'm sure if i poked them with a pencil or something it would feel similar to 'numb'.

the feeling is sometimes in my calves too.

i'm not convinced it's a 'geometry' thing -- i'm guessing i just need to rest. i sprint to "work" and then spend 8 hours on my feet as a waitress, my best guess is i'm simply fatigued... i just want to make sure it;'s not something else... thanks!

You maam are my hero!

Yea take the suggestions others have given of taking a few days off of the ride. Riding (sprinting even) that far and then standing/walking for 8 hours would prolly make anyones legs go numb. Give yourself a little more time to get to work so you can warm up for 10-15min before making the sprint.

I would look into bike fit issues, as well as posture on the bike.

A long while back, I was getting numbness in my toes that came from having my seat too high. I have a recurrent problem with numbness in my pinky finger, which occurs when I slouch too much at the computer--it is a mix of bad posture at the neck shoulder area and too much time using a mouse.

Alternative interpretation: I get a tingling sensation in my calves on the first major effort of a ride, whether it is a sprint or a hefty climb. This seems to be from an expansion in the blood vessels. I don't worry about this, since it is a light sensation (at or near the skin) and lasts only a minute or so.

You could test if this is the case by going for a ride where you go gently for a good 20-30 minutes, then sprint like the devil for a minute or two. Does it occur then?

Good luck!

I have noticed the same sensation at times when I have been pushing it really hard. I weight train as well as ride and when I have overdone it, my upper thighs will also get "tingly" or "numb" when seated for awhile. Some rest and good nutrition has always solved the problem for me. Best of luck to you!

Just a possibility:

Thanks to Hitchy, I've recently become aware of an unusual syndrome
in which the external iliac arteries can be temporarily "squished" or kinked
when cycling. This is more common amongst cyclists than other sports people.

The external iliacs become the femoral arteries which mainly supply the muscles
on the inside of the legs.

If blood supply is temporarily impeded, temporary claudication can occur, which often presents as a vague, "cramping" sensation.


JUST A SUGGESTION