It's cheaper and more useful to just track something like your 5k time over time. If it's meaningfully improving from year to year, you're improving all the th

It's cheaper and more useful to just track something like your 5k time over time. If it's meaningfully improving from year to year, you're improving all the things you care about. (The best way to improve that is to slowly increase your volume of cardiovascular training over time, with at least 80% being zone 2 work.)