I’ll never forget it. I was sitting at my desk after a morning walk, glanced at my Apple Watch, and there it was: “VO₂ Max: Below Average.” At 65, that stung. My first thought was honestly just — well, I’m old. This is what happens. Maybe I should accept it. But I’m an IT guy. I don’t accept error messages. I troubleshoot them. So I started digging into what VO₂ max actually meant, whether it could change, and what I could do about it. What I found surprised me — and over the next several months, I turned that Below Average rating around without ever stepping foot on a treadmill.…