I always like to dabble with gadgets! Those who know me know how I love my Suunto Ambit 2, to monitor my mileage, ascent, average HR etc.
My new favourite tool, however, is a great little app called iThlete. Its a monitoring tool that measures a physiological variable called HRV or heart rate variability. You need an iPhone or Android phone, the $10 app, and a compatible HRM (of which there are a few). Fortunately I have a great little blue tooth HRM called the ViiiiVa from 4iiii. It allows my iPhone to connect directly to the strap on my chest. It interacts efficiently with the phone - and will work with such apps as Strava, MapMyRun etc.
Heart rate variability is a measure of the small variations in time between heart beats.
You may have noticed that your heart rate subtly increases with a deep breath in, and slows when breathing out. If there is a large change, the HRV is high, and if there is very little change, you have a low HRV. Simple!
Physiologists have shown that the HRV is a pretty good indicator of how rested, how fatigued, or even over-trained an athlete is. The tool is being used by coaches and athletes to assess readiness for hard workouts, and to assess when a rest day is a better idea.
The iThlete app takes 1 minute each morning to assess my HRV. A numerical value is presented along with a green light (good to go), amber light (train easy) or red light (time to take a day off) indicator.
I'm finding it to be a great little tool, with sometimes surprising results. A couple of weeks back I got the green light to go, despite waking up feeling pretty sore and fatigued. Once I got out there, in fact, I ended up having a great training session, and feeling good. Without the HRV, I'd likely have taken a rest day.
2 days ago my HRV reading was down, with amber values, despite feeling pretty good. Sure enough, 24 hrs later I had a sore throat, and was feeling pretty crappy. I had taken a rest day due to the HRV, which turns out to have been a great plan, given the mild sickness. I will wait until I see my HRV bounce back, before resuming training.
So there we go - a nice little app available on the app store if you're in the Apple eco-system; and the Viiiiva HR strap is a great addition if you own a bluetooth compatible phone.