The older you are the better you'll be at grinding out the miles.
Certainly the miles build up more peacefully now (at 66) than they did at 36.
Though (even) more slowly.
But recovery takes longer and is less pleasant, with less of the "lovely achey" kind of feeling, and more of a nauseous/ill/wrecked/hungover one instead. Which is disappointing, compared to the ok-ness of the riding.
