Definitely. My commute is 28 miles RT, and I've got 56 years on the bones. I can do two days in a row, but really feel a need for a break by Wednesday. It would probably be doable physically, but not enjoyable. I have a "suit job" that requires a fair amount of travel around town for various appointments, so I do my best just to schedule those appointments for the days I've decided not to ride. I also make use of those days to swap out the office wardrobe.

I suspect it would be easier if I had one of those jobs where people get off work when it's nice in the afternoon. Unfortuntely, the ride these days is in darkness both ways. That has a niceness all of its own, but it also seems to drain me more than riding in daylight.