I think English subtitles can be very helpful at first-- it is like working on reading and listening at the same time.  Later, when you find there are only a few words you do not know, then working on listening by itself can be good. That is my advice if you only want to listen to something once.  

However, I think it is also helpful to listen to a video twice or even three times.-  I listen once just listening with no subtitles and no looking up, and listen another time looking everything up. (And sometimes a third time with no subtitels again.)   I am undecided which I think is better to do first and I tried but have been unable to find research on it.  I believe when I do not use subtitles I pay more attention to the faces and mouths of people and my brain also works hard just on paying more attention to the sounds and the meanings.  

Your brain learns from comprehensible input.  At the level I am at now, I can understand the vast majority of what I hear without subtitles, so when I do hear a word that is unfamiliar to me I can make a mental note of it and sometimes understand it just from the context-- learning it more like a child would.  At earlier levels, adults can use the language they already know as an aid to make it comprehensible.