Thoughts on 3 things that “Numbness” could be attributed to from a body standpoint:
- True Neurological Numbness is caused by a disruption of sensory nerve transmission causing complete loss of neural signal. Pins and Needles on the other hand are caused by an intermittent signal.
Application: Too much pressure through the wrist (think carpal tunnel) could be a reason for numbness into the thumb, pointer and sometimes middle finger.
Too much pressure through the balls of your feet can increase pressure in the inder digital nerves in the feet
(Photo Cred: https://www.physio-pedia.com/Morton's_Neuroma)
Too much pressure through the saddle region (Other than the Pudendal Neuralgia, as commented on another thread) can cause pressure through the sciatic nerve,
Solution: Bike Fit (There are a number of good links in the thread above)
#2 Muscular in Origin
I have met a number of people through my career that state they experience a sensation of “numbness” but fail to present an objective measures that prove true “Neurological” Numbness. These would be Nerve Conduction Tests coming back normal, No loss in light touch sensation, No loss of power, No loss of deep tendon reflex and no obvious traumatic injury leading to severing of the associated nerves.
Can I suggest that some “Numbness” is actually a subjective description of a muscular trigger point type pain.
For example: As most of us are Cyclists, and Triathletes we are gripped onto our bars (cylists) or folded into an aero position (Triathletes) and we are using a large muscle called the Latissimus Dorsi (Lat) to stabilise our torso, or to pull the bars towards us in a sprint. During a Sprint Build Phase is it possible that the Lat will be overworking a significant amount leading to fatigue? Eventually the muscle cannot release (repolarize depending on who’s theory you are applying) and an athlete can develop muscular trigger points that are referred to by the athlete as pins and needles in the 3-5th digits in the hand
The “Muscular in nature” numbness can be explored by looking at the work of Travell and Simons
Application: Learn about your body and the different areas of soreness you have by visiting a knowledgable Health Professional (Physio, Chiro, RMT etc.) and get them to teach you. Or this is a resource I found on quick seach ( http://www.triggerpoints.net/ ) that might help.
Solution: Book an appointment with your Healthcare / Maintenance Team and ask 100,000 Questions. Always be a student of your body!
#3 The 3rd potential body cause of “numbness” could be Vasular in nature (Blood Supply) this option is a bit more serious as it can cause the body damage and often requires imaging (Vascular Ultrasound with or without Dopler) to assess extent of the problem. If the above 2 suggestions aren’t helpful seeing your GP and letting them know you are a cyclist, the symptoms you are experiencing, and whether or not you have tried to change your setup (with the assistance of a qualified fitter) or worked on your own body (with the assistance of your healthcare team) will help them point you in the right direction. There have been professionals who have had to go down this track for treatment but you would assume they tried to rule everything else out before operating.
Hope this is helpful. Happy to chat more about this sort of stuff.