Well, the century was the longest ride I've done outside. I rode 65 kms on Saturday, then the century on Sunday. Two weeks ago I rode a metric century ... half outside and half inside on the trainer, and then the next day I did another 50 kms outside. And I've been riding my trainer an hour or two a day for quite some time.
So it isn't as though I've been off the bicycle for an extended period of time or anything ... but it has been just over 2 months since I've done my last century ...... maybe that's too long between centuries for me!!