I was just sick for 2 days and spent about 1.5 days sleeping (like I literally slept 18-19 hours on one day, and probably 12-13 hours the next) - I am now recovered and I feel a couple of years younger...so I guess it goes both ways
To your point, I had a season of extremely hard work (for me) where I was on two timezones (one in Europe and one in the US) and ended up in a situation where, due to severe jet lag, I would go to bed at the right time for the timezone I was in, sleep for 12hrs, and wake up *more exhausted* than when I went to sleep. Very demoralizing, but this continued for weeks. Eventually I decided to take a sleep-cation. I went to a friend's house who generously offered a private room. I prepared a couple of meals in the fridge and proceeded to sleep as much as I could for the next three days. I probably slept more than 20 hrs per day, although I didn't necessarily have very long stretches. I only needed like 4-5 meals over that time. It really took me out of a negative spiral and got me back on track. If you actually can sleep, I've seen this approach help people "reset" on their sleep and then get more regular benefits from their sleep hygiene.
