I am i feel. I walk everyday, work 60ish hrs a week etc. To prep i am lapping in a pool a couple times a week. Do you feel that is adaquate or perhaps something additional?
That’s fine. Snorkeling laps with a kickboard a mile at a time several times a week is how I got into shape after I started diving out of sheer necessity. I was a sloth!
BTW, I got certified at 47. 49 now.