In my view, it definitely has a relation to BioAge. My wife, for example, at 68, feels like 40, and her vascular age measurements confirm that (and her looks, too). I, at 66, feel most of the time somewhere in my mid-forties, if you ask. But there are days when I feel like 80. But those are rare and exceptional (and most of the time there is a reason for that. So, yes, how you feel is a very strong indicator of biological age.