I'm 53 years old now, but when I was 45 our daughter was only 14 years old. Most of the change in my life since that age has been caused by becoming an empty nester.
But back then a Thursday-Friday-Saturday would involve:
one or two mornings of surfing,
another morning working out (bodyweight exercise),
a taekwondo workout,
an hour or two each day of maintenance or repairs around the house,
an hour each day of writing,
30-60 minutes each day of napping,
probably one day with an hour or two of errands (usually on a weekday, almost never on a weekend),
maybe a 45-minute spouse walk one evening,
lots of reading of the Internet and books, and
chatting with my spouse.
Maybe there'd be a lunch with a friend or a group in there... usually 3-4 times per month. These days there might also be a phone call or Skype interview with someone about the blog or whatever writing project I'm working on.
Of course eight years ago at least an hour of each of those days would've involved teen drama and/or angst, and my daughter and I would've surfed together on Saturday morning. These days, frankly I'd be willing to let a little drama & angst back into my life if it meant we could do more surfing together.
Curious about this as well. There is research that shows that early retirement people are more likely to get dementia.
I'm afraid that you're gonna have to back that up with a link to peer-reviewed research published in a professional society journal.
Most of the "research" on the unhealthy effects of ER has been generated by people who became unhealthy at work and immediately retired to salvage what they could of their lives.
Personally, I bet being retired and finding out that you're heading into dementia is
still better than working. But I could be biased... or just suffering from mild cognitive impairment...