Tremors can be pretty disconcerting, especially if you're an experienced fitness person, as it seems you are. I get tremors when I am overtired and stressed. They generally get worse with worry, but they get better with rest and a regular schedule. Sometimes when I am talking to someone and getting animated, my left hand will begin to tremble and shake.

I used to lift religiously and was 150% into fitness for years, so I also feel I have a good sense of my own body. Tremors -- especially when they come out of the blue -- can be worrisome. I've also got weakness in my left hand. I've been hit in the head more times than I can remember -- assaults, car accidents, falls, sports injuries -- so maybe that's what causes it, maybe not.

You may want to check with a neuro about it. I haven't done so, because I'm leery of them after some really bad experiences -- and (full disclosure) I'm also a little concerned that they might "find something" that I don't want to deal with. I've made a pact with myself that if they ever don't go away after good rest, good food, and regular exercise, I'll seek medical attention, but for now, just taking care of myself and not worrying about it is my #1 approach.