In the McCleland household this is a contentious issue. Always was; always will be. This bone of contention raised its head some 20 years ago when I was training heavily in order to achieve my personal best [PB in runners-speak] over all distances up to and including a marathon. Anal would be too blasé an epithet to describe how I measured my runs: weather conditions, temperature, splits per kilometre, weight loss on the run & controversially from Janine’s perspective, my daily heart rate. Science has now come to my rescue and vindicated my standpoint. At the extreme, it also issues a warning when one’s resting pulse is too high. What does science now tell us?
Main picture: An X-ray of the heart with veins coloured blue and arteries red