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.
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.