How do I reduce the file size of Windows 10 Game Bar recordings?

I use Windows Game Bar to record my screen (and not necessarily for Games). The size of the file that comes out, however, is sometimes outrageous. A 5 min recording takes up about 200 MB! Recently, I recorded a one and a half online lecture and the file size was about 8 GB; it reduced to 3.2 GB after compressing!

How do I reduce the file size? Video quality settings under "Game Bar Settings" in Windows 10 is set to 30fps and "Standard" (Standard and High quality are the only two options).

Solution 1:

I used FFMPEG and used the following command:

d:\FFmpeg\ffmpeg.exe -i "issue12.mp4" "issue12-1.mp4"

With this, there is a quality loss, but file size dropped from 68MB to 2MB for a 2 minute video.

Solution 2:

I cannot provide an explanation as to why, but here is a technique that worked for me.

Get any video editing app, and trim a few seconds off the start or end.
I suppose this edit causes the app to change the formatting of the video, but either way, you should have a video that is not abnormally large.