Where I worked, the typical, normal schedule was two afternoon-evening shifts, followed by a mid-day and two morning shifts, OR, two afternoon-evening shifts, two morning shifts, and a mid- night shift. (2300-0700)
You could sleep all day after your mid, and still had 2 more days off.
The reason I retired a year before I was required to, was that I was scheduled for 6 day work weeks, with only one day off, and that was to train the new folks, who were mostly off-the-street hires with no background in aviation. That was more exhausting than just working traffic.
When I was hired by FAA in late '70s, with few exceptions, most hires were either ex-military ATC, or instrument rated pilots like myself.