i seem to be stiff for some odd reason when i went into my dream the other day, when i tried to run, it seemed almost like my whole body glued in place, and even though i could move, it was very VERY slow. like im stuck in peanut butter. 
cause i was trying to run away from someone on the side walk, that happened to me. but it went away if i went on all fours and ran like a animal. (wolf, bear, etc.) does anyone know why this happened? thank you! 
Sometimes you can feel the sensation of sleep paralysis in your dreams. You can over come that by just by rememebring that your not tied down by your physical body.
It’s a common dream theme for one reason or another. I don’t know if there is an official explanation other than distorted physics due the the dream. It could be SP, it could be muscles tensing or a whole bunch of other things. The fact is that it is normal. When it happens in an LD, you can try things like voice commands, thought commands, flying and others.
Was it a LD or a NLD?
The exact same thing happened to me hundreds of times, since early childhood. Sometimes it’s when I try to reach something, but most of the time it’s when I try to escape something (get out of a place, run or avoid somebody). I don’t know what causes it. It could have a psychological explanation since most of the time it occors while I try to run from something (exactly like what you describe). Or it could have a physiological explanation since I often woke up in SP when I woke up while glued in a dream. One thing is sure, it’s that it’s normal and quite common.
Anyway, this happened so many times that it became a HUUUGE DS.
I usually don’t experience this, although I had one dream where for some reason I couldn’t take hand out of the pocket… But after putting much effort to pull it out and with very unpleasant feeling I made it. The reason why this happened I don’t know but I understand what your going trough, even though I can’t imagine how it would be with the whole body…
wega, i dont know, but yeah this does happen to me A LOT so it is a DS. it only happens to me when im running away from something for some odd reason though.
Happens to me all the time, especially in DEILDs because in DEILDs I usually start the dream in my bed and I struggle to get up or something. One time I was unable to look up. I think the best way to counter this is to just relax and remember that it is a dream and you have complete control.