I think its important to continue to do what you've always done. It's also true that you will get the body you crafted in the first 40 years.But some things will always get in the way. When I was 37 and rebuilding my MGV8, I was working 5 days. I would get home from work, grab a quick meal and be in the garage by 6.30pm, and stay in there until 10.30/11.00 very often. Weekends were usually 08.00- 6.00pm straight through. Even through winter. Now I get tired by 2.00pm. Tiredness equals mistakes, so knowing when to stop matters.
It also affects travel, and although not so much, I can tell that my stamina isn't what it is. We have done Torquay and back in the day three times. First time in my MG Metro, way back and it was fine. Much later in 2002 in my Golf TDI and although a much better cruiser, I could sense less stamina. A couple of years ago in my GTD, again, a much more composed car, but this one really tired me out. So I think the one thing which does affect mobility and agility is diminshing stamina.
I don't suffer not sleeping. I still sleep well, and my often 'wake up time' is 09.00/09.30 and that is effortless. Most 'old' people we know are more crumbly than we are, both in mobility and medication. I think that commuting by train, and occasional hiking has really made a big difference. Those we know with car dependency as a norm, are often now shuffling examples of how not to get old gracefully.
But none of that will prevent a stroke.
