My coach has switched from the "kinder, gentler" style she used while I was doing chemo back to her "beat the geezer like a rented mule" mode. This build has included two days with uphill anaerobic running intervals and tomorrow is another set but on the bike. Plus stretching out my running workouts, up to three hours now. Plus strength work. Sheesh. But my mojo's coming back.
I did have a glitch, though. My first race back ended in a DNF due to my lower back locking up on me. I could've death-marched to the end but it would've been way past the point of diminishing returns.
There's a 27-mile trail race in two weeks that I'll probably do. It'll be my first race in 70+.