Adding closed captions to a course already uploaded?

Hi all.

We have already created and uploaded our Rise360 course, but we have now been asked to provide closed captions for each video. Are we correct in thinking that we will need to go back into each video and create CC and then re-upload the course? 

If this is the case, what is the quickest and easiest way to create CC for each video?

Many thanks!

Lindsay & Melissa