Ever had a sleep paralysis experience and what do you think of it

I haven't had one myself but my cousin had one and told me about it. He said he got lifted up off his bed like a feather and he could see black figures moving around in his room. He's a big dude like 6 foot 200 plus pounds. I know he wasn't lying to me because we are close. Obviously you don't have to believe me. I hope it doesn't ever happen to me. It did freak me out a bit when he told me. I mean if they can lift him off his bed that easy they're just gonna send me flying out the window. I'm not a big guy ha.