I stumbled upon an acronym I hadn't heard before - HRV. I was listening to the Ben Greenfield Podcast and a guest mentioned tracking her HRV. HRV?? What's that? After a quick google search I came across this:
"[HRV] is the physiological phenomenon of variation in the time interval between heartbeats. It is measured by the variation in the beat-to-beat interval." - Wikipedia.
Furthermore, "Exercise training may decrease cardiovascular mortality and sudden cardiac death. Regular exercise training is also thought to modify cardiac autonomic control. Individuals who exercise regularly have a 'training bradycardia' (i.e., low resting heart rate) and generally have higher HRV than sedentary individuals."
So this got me interested and of course I had to see what my HRV was so the next logical thing was to see if there was an app for that. Of course there were several apps. The one I picked out was Elite HRV (free) which pairs with your HR monitor and will analyze your heart rate and give you a 'readiness' score. The score, 1 through 10, is based on how stressed out you are (how your HRV compares to the previous day). If you HRV is high then you're supposedly at a low biological stress level and ready for a demanding workout. If your HRV is trending low then your body is stressed and you should probably take an easy or recovery day.
I've incorporated this into my morning schedule, post coffee, a 2 minute 30 second reading to see how I'm trending during this taper week. I'll be testing it out before and after my 50 miler and then have an idea if this is a biomarker worth tracking.