Just curious if anybody has a set routine or a go-to exercise to stay sailing fit. Or whether just general overall fit and healthy is enough.

I would think general fitness with maybe some bias towards chin-ups or pushups would be enough (not that this is what I do, but probably should )

I used to have a dummy side deck for hiking too. These days I just row about and ride a deadly treadly.

Before I discovered beer during racing season I set my alarm to ring every hour during the day. Each time it rang I would stop what I was doing and do 10 super slow pushups. Squats then situps. 10 isn't hard to do but every hour that's 100 per day. It made winding winches and pulling sheets much easier. Accidental exercise too, like Mr miyagis idea. Row out to boat don't use outboard, lift anchor by hand, polish decks by hand not electric buffer (wax on wax off) , park at far end of car park not close end, carry stuff to boat don't use trolley... Etc

yoga great for flexibility your probably already strong enough