I have something that sounds similar. Manifested as classic golfers but i was sceptical of that as i hadn't had a trauma, volume was steady and it would come and go. It came on at the same time as neck and shoulder issues and i suspected it was related.
Physio did a bit of prodding and reckoned it was down to knots in the forearm, which is quite tender in the belly, and diagnosed foam rolling and self massage. It will disappear completely but temporarily after a bit of poking and rolling.
I've been climbing at full intensity (on physio advice) with a bit of discomfort occasionally but it hasn't gotten any worse.
Reckon it's the sort of thing one of those armaid devices would sort out, and there are a lot of folk thinking they've got golfers when they haven't.
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