Resting heart rate is negatively correlated with cardiovascular fitness: the lower, the better. So far as I know, the point of measuring lifespan in heartbeats is that tachycardia does in fact kill you that much faster. I am not a medical professional, and it’s probably not wise to take “conservation of lifetime heartbeats” too literally, but that’s the general idea.
I’m fairly sure it isn’t proportional: someone with a heart rate of 40bpm isn’t going to live twice as long as someone with a heart rate of 80bpm. (But might well live 3x longer than someone with a heart rate of 120bpm, which I guess would indicate a serious medical problem.)
I’m not an expert, though, and will gladly be corrected on this.
Resting heart rate is negatively correlated with cardiovascular fitness: the lower, the better. So far as I know, the point of measuring lifespan in heartbeats is that tachycardia does in fact kill you that much faster. I am not a medical professional, and it’s probably not wise to take “conservation of lifetime heartbeats” too literally, but that’s the general idea.
I’m fairly sure it isn’t proportional: someone with a heart rate of 40bpm isn’t going to live twice as long as someone with a heart rate of 80bpm. (But might well live 3x longer than someone with a heart rate of 120bpm, which I guess would indicate a serious medical problem.)
I’m not an expert, though, and will gladly be corrected on this.