"None the Xer" means "not any more X."
A common expression is "was none the wiser" - this means the person didn't get any extra knowledge about it, or more accurately, didn't know anything about it.
For example, Mary often slipped out her bedroom window at night to meet her friends, and her parents were none the wiser. (They didn't know.)
In that example, after working, she was not any more sleepy afterwards than before. She had no additional sense of feeling sleepy. We don't how if she was very sleepy or barely sleepy before she started working.
Student or Learner