Originally Posted by
tomato coupe
I would say the old rule of thumb doesn't work for you, since 220 – 61 = 159, which is significantly lower than 173.
Fair point. I should have summarized my usual excessively overwritten post. I just regarded the 220 minus age formula as a good enough ballpark. It's close enough considering I came from a background of excellent physical fitness in my youth, but now with some health issues and medications my HR and BP can fluctuate quite a bit. There's no formula that would apply to me in all conditions, so a ballpark is good enough. From there I can fine tune my expectations based on other factors I described.