I found this post when I was looking for an answer to this very question, after waking up around 3am with a foot and leg cramp (right side) following a nerve conduction test the previous day (the test was only on my hands which were not touching any other part of my body).My whole body felt sore. I went back to sleep and arose at my normal hour. My right shoulder/neck felt like it had been hit with a baseball bat...very stiff and sore. Right hand and forearm was also very sore and painful.I had no such symptoms before the test. In fact, I was feeling remarkably pain-free except for some pain and stiffness in my hands.My right hand was deemed "moderate" nerve damage and the left was "mild to moderate."The median nerve runs the length of the arm through the carpal tunnel so it makes sense to me that I would experience shoulder and neck pain after the nerve had been stimulated by the test.The leg pain seems strange, although I have had chronic issues off and on with my right side...neck/shoulder pain, leg pain (mid-thigh, large muscle), right hand/wrist.I'm sure it is all connected somehow but I am not an expert on anatomy.It was good to know that I am not alone, however, I was not warned at all that there would be any side effects.I feel bad for people who had much worse side effects (crawling to the bathroom).Since my nerve conduction study was only on my hands and only moderately painful I can just imagine the impact of a nerve conduction study that was either more intense (voltage?) and/or on a larger muscle group.I find the crawling part completely believable based on my limited experience.I feel like I've been in a fender bender where I got hit with "moderate" force (20-30 mph)...just enough time to see it coming, tense, and really feel it the next day.

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Nerve Conduction Test Side Effect? - Neurology - MedHelp