That is one of the reasons I continued to work til just before my 70th birthday. I handled the contract work for a consulting engineer so we had flexibility as to the when. I worked 3 days a week (Tues thru Thurs) for about 8 or 9 months of the year. We could schedule the work and block big chunks of time off so my wife and still could travel for 2-3 months each year. Plus I loved the work, it was physical which was great for me....didn't have to bother with the gym membership. And they paid me for it. But it reached a point where the physical toll had become too great and it took me the Friday and into the Saturday to recover enough to other things I love like hiking and bike riding. I started to resent when Tues rolled around and I had to begin the cycle again.....so I pulled the pin.