A younger man? - I have enough trouble keeping up with the old one I have got!
Nothing vital wanes as they age, in my experience!
Talking about taking a sabbatical at 50 while you are still relatively fit - I actually completely jumped off the professional wheel at that age. I re-trained in photography and pursued 10 years of working in arts outreach, running singing workshops, picure editing for a magazine, general photography etc. - had a great time and it was a huge tonic and what I had always wanted to do. More or less retired now - just take on projects that I really like now and again, but also help to run various arts projects voluntarily, including a villages choir.
My Ds say that it was a great example to them not to get stuck in a rut and that anything is possible - so that was another positive spin-off.
I was very lucky that my OH was happy to put up with the relative poverty that my decision resulted in.