Garmin HRV Stress Feature
I believe that the Garmin HRV Stress measurement feature is completely under-utilized. Garmin has a LOT of features on their head units and watches that are underutilized. When Garmin purchased FirstBeat, the premier company that has studied Heart Rate Variability and its’ applications for health, I thought they would bring this information to the masses. Well, it’s there, but it’s still not well-promoted. This blog post is the first of many that I’m going to use to study HRV Stress, long-term.
What is HRV (Heart Rate Variability)?
I have been studying Heart Rate Variability since the early 2000’s, when the technology was paired with Suunto products. For years, Polar Oy was considered the leader in heart rate measurements, but the Suunto T6 really impressed me with how they used FirstBeat’s technology to explain cardio fitness. The distilled version of Heart Rate Variability is this;
“NO TWO BEATS ARE THE SAME.”
A heartbeat is usually pegged to the ‘R’ wave, which is the contraction of the Left Ventricle. The original heart rate measurement looked at a rolling 6-second average of heart rate, to come up with a value, usually between 35 and 220. While we still use that measurement of exercise intensity, the more modern way is to look at the millisecond variation between each beat. When a heart is ‘happy’ or under little stress, it basically beats when it wants to. When a heart is under more stress from exercise intensity, the variability diminishes. The DELTA between beats, over time, is called the “Root Mean Square Standard Deviation”, or “RMSSD”. Heart Rate Variability (HRV) measures that Delta, and runs it through an algorithm based on FirstBeat’s Two-Plus Decades of Science and Publications. The solution, in this case, renders a ‘Score’ between 0 and 100, to assess an individual’s preparedness for exercise.
I have been a fan of a further evolution of this measurement via DFAA-1, but this measurement is about general health and wellbeing.
The Garmin HRV Stress Test
I use a Garmin 1030, but the Stress Test can be found in most of the modern Garmin head units and watches. You will need a chest strap, and honestly, a quiet place where you can stand still for 3 minutes. THERE SHOULD BE NO DISTRACTIONS. If the head unit or watch is set to send and receive messages or news clips, the test will fail. If you like soft music, headphones or earbuds might be appropriate. No kids, no pets. Just you, your head unit or watch, and a brief period of time.
This video explains how I get to the HRV Stress Test feature on my particular Garmin. Once the test is over and I have a result, I usually take a screenshot of the results.
Results
The goal with this series on the Garmin HRV Stress Test is to determine whether the HRV Stress Score corresponds to my fitness and training on the bike. The quick, short summary of the scores is like this: When the score is LOW, Garmin claims that you might have more success at a moderate or high intensity or high volume day. If the score is in the Medium Range, LSD or ‘Zone 2’ might be appropriate. If the score is HIGH, well, light exercise or no exercise is appropriate.
I intend to look at the ENTIRE Garmin Connect Ecosystem to determine my preparedness for exercise. This includes Garmin’s Sleep Score, the Body Battery, and even Garmin’s Hydration Tracker.
Why?
Because it’s all in one ecosystem via Garmin Connect. A combination of rugged wearables, head units, and software. Furthermore, I don’t think anyone has objectively followed these physiological measurements like this and presented them this way. The information has been there for years, but I honestly don’t know if the information is empirically valid or not. The science and the papers say ‘yes’, but the individual experience just has not been presented on the internet.
Let’s see where this information leads. Thanks for reading, and…
ENJOY THE RIDE!