--during certain parts of my exercise routine.

They do not always occur, and do not occur in the same wasy always when they do, but I get a range of tinglings, pricking, feelings of warmth/cold, and the like when I am really trying to extend and work certain body parts.

Fortunately, so far none of these have been permanent, and they eventually fade, though sometimes it takes days.

I've written before that I am fiarly convinced that those of us with any kind of nerve damage are and will be more prone to the type of compressive effects that Mrs. D describes--the added mechanical pressure on already damaged nerves (the so called "double-crush phenomenon") produces symptoms in us that a "normal" person would not likely get.

Also, keep in mind that healing and reconnected nerves cause their own weird sensations. As the nerve growth cones fight through other tissue trying to re-establish connections, they are very vulnerable to compressive effects, and often produce weird feelings. Eventually, the brain learns how to better interpret these, but that may take quite a while (and it is unlikely that the re-wiring will be in exactly the same configuration as the original, and it probably won't be quite as complete, either--"slow, partial recovery" is more the way things seem to go).