I had the same problem, a notable decline in my VO2Max that worried me enough that I had myself tested on a treadmill. It showed my VO2 Max was just fine -- at least 20 points higher than Apple Watch. Have you seen any studies that demonstrates Apple's VO2 Max is accurate?
One thing to watch out for with Apple Health's VO2 Max estimate is that rucking will likely plummet your score. Your Apple Watch has no way to know you have extra weight on your back so it just assumes your higher heart rate for a walk/hike/run is because you're less fit. I'd recommend tracking rucks as something generic like "Mixed Cardio" as VO2 Max is only calculated by walking/hiking/running in Apple Health.
The Long Game 157: Increasing Your VO2 Max, Couple Dynamics with Kids, Optimization, Rest
I had the same problem, a notable decline in my VO2Max that worried me enough that I had myself tested on a treadmill. It showed my VO2 Max was just fine -- at least 20 points higher than Apple Watch. Have you seen any studies that demonstrates Apple's VO2 Max is accurate?
One thing to watch out for with Apple Health's VO2 Max estimate is that rucking will likely plummet your score. Your Apple Watch has no way to know you have extra weight on your back so it just assumes your higher heart rate for a walk/hike/run is because you're less fit. I'd recommend tracking rucks as something generic like "Mixed Cardio" as VO2 Max is only calculated by walking/hiking/running in Apple Health.
Welcome back! Hope the baby is healthy!