What’s the best protocol for measuring heart rate variability (HRV)?
What’s the best protocol for measuring heart rate variability (HRV)?
no amount of continuous data can beat a good protocol
To answer this question we need to remember what HRV is about and what our goal is when using HRV.
HRV is our stress response, when measured at the right time.
Measured at the right time means:
at rest
far from stressors
Why?
Measuring during or close to stressors turns any normal physiological response into something pathological (this is what ‘real time stress monitors’ in wearables are doing, check out this blog as well).
In reality, it is perfectly normal for physiology to be affected for a while during and after exercise.
Morning measurements allow us to measure our resting physiology as far as possible from the previous day’s stressors and after the restorative effect of sleep, and as such, I consider them the ideal way to capture our stress response.
A late dinner, or late exercise or simply having more carbs for dinner, something we might be doing on a heavy training block, might result in increased heart rate for several hours during sleep, which is no problem, but would be captured as a negative response by wearables measuring during the night. Often, night data is more tightly coupled with our behavior than with our stress response, and therefore is less useful for daily guidance.
Finally, morning measurements allow us to measure in a body position other than lying down, which is key to capturing more useful data.
In particular, measuring our HRV while sitting or standing exploits the orthostatic stressor (meaning that by changing body position, you trigger a physiological response, and the body has to quickly re-normalize). This procedure makes the data more sensitive to stress, allowing us to capture changes that are not visible in data collected while lying down and in particular during sleep.
Especially for endurance athletes with low resting heart rates, measuring while sitting (or standing) is a good idea. At times, the body needs to be challenged for us to better understand its response, and this is not the case during sleep.
No amount of continuous data can beat a good protocol.
Other articles on this:
Heart Rate Variability (HRV) measurement timing: morning or night?
Heart rate variability (HRV) measurement position: lying down, sitting or standing?
Marco holds a PhD cum laude in applied machine learning, a M.Sc. cum laude in computer science engineering, and a M.Sc. cum laude in human movement sciences and high-performance coaching.
He has published more than 50 papers and patents at the intersection between physiology, health, technology, and human performance.
He is co-founder of HRV4Training, advisor at Oura, guest lecturer at VU Amsterdam, and editor for IEEE Pervasive Computing Magazine. He loves running.
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Twitter: @altini_marco.
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Hi Marco,
thanks for your insights.
I have a question regarding the „far from stressors“ part. I am an anxious person and, consequently, at times also suffer from sleep problems. In my case, the anxiety manifests itself more in the later part of the night and in the morning.
Currently, I measure in the morning. Should I maybe transition to measuring before going to bed?
I am seldom nervous in the evening , which also manifests itself in my generally not having problems falling asleep. It is staying asleep that is the issue when in an anxious period.
Do you have any experience in this regard?