After catching a virus I have been down for quite some time. In this period I learned that heart beat is a better indicator of how you are doing than your subjective experience.
I’m not talking about feelings whatsoever, neither about beats per minute (BPM). I’m talking about heart rate variability (HRV), a metric I didn’t know before but I will keep using for training purposes from now on.
We often think of our heart beat following a regular beating pattern and talk in terms of heart rate. This is true to a large extent, but incomplete. There are small variations in intervals between individual heart beats.
This interval varies, typically by a few milliseconds, and is called heart rate variability or heart coherence. It indicates very well how the body is coping with stressors.
A coherent heart rhythm is defined as a relatively harmonic signal with a very narrow, high-amplitude peak in the low frequency region of the power spectrum and no major peaks in the other bands.
Left the valley of disappointment pic.twitter.com/yafMlvruPr
— Gijs Heerkens (@gijsheerkens) May 5, 2022
HRV at rest is very individual so when measuring it you should always look at variation against your own baseline instead of comparing it to other people’s HRV.
The value of your HRV at any given time is affected by activity in your autonomic nervous system.
Essentially fatigue from physical exertion, stress, lack of sleep and a range of other factors will lower the HRV value.
All the things we do during a day are stressors your body tries to handle:
- Poor sleep
- Social interaction
- Eating garbage
- Reading
- Getting sun
- Walking
- Riding bicycle
- Household chores
- Watching TV
- Working out
Rest, recovery and good nutrition to fuel these will raise HRV.
From an athletic perspective HRV is a great overall physiological marker. A relative high HRV indicates that a person is fresh and ready to perform at its best.
As you get fitter your baseline HRV value may also rise, so this is a reasonable guide of overall fitness.
I’m using Training Today app on my iPhone to determine if I’m ready to train. This app uses the Apple Watch to monitor HRV and is comparable with Garmin’s Body Battery.
The Apple Watch automatically measures HRV when I am in a relaxed state. It takes about ten data points a day to get a good trend view.
Training Today takes these readings and compares them against a 60 day baseline HRV to produce a score that can be used as guidance in deciding if you are in good condition to complete an activity (RTT, Readiness to Train).
The scores are linked to heart rate zones in its recommendations.
Whilst the science of HRV has been understood for some time it is with the advent of wearable technology that its application in sport has become more accessible.
Finally a good reason to have a smart watch.