it could be muscle spasms, or gas? I get those too but it is usually one of the 2 I listed above. I have poor circulation as it is, so crossing my legs for long periods of time causes me to have spasms.
Oh my gosh sometimes I get the weirdest gas bubbles and it honestly reminds me of when Aspen used to kick me.
That used to happen to me alot when I'd cross my legs.
Like I'd get weird twitch-like spasms just like if my eye were twitching or something.
And just like you, I'd uncross them, and it'd stop.
I'm sitting there all wtf-like, and so eventually I just stopped crossing my legs cuz it got annoying after a while.
It'd happen to me almost every single time.
Weird.
lol