Last night, My mentor talked about "What is good vid ref ?"
We tend to think it has dynamics motion, such as Jim Carrey. Yes, It is true( Of course, Jim is a best actor) but most important things is a "texture".
Even though body motion is statics, If you could make or catch a "texture", that is definitely the good vid ref.
So what is the "texture"?
look at around 0:03.
He grab a rock, then he search a good point to get a grip. and at the same time he find out good foot position. In other word he find a balanced position.
Around 0:10 again he try to find a next good position.
These are very detail, indeed but it makes 'believable' feeling in your animation if you put these in.
So if you want to make a "believable" animation, pick a "texture" and put it in yours.