Sleep efficiency vs. heart rate

[Dominique]

On a couple of nights, I logged my heart rate with my Mio Alpha HRM watch and I compared the results with the sleep log I get with my Fitbit One. In both cases, these were "good" sleeps, as deemed by Fitbit (98-99% "efficiency"), and their duration was about the same (about 7 hours).

During the first night (November 26, 2013), I used the Runtastic Pro app on my Android smartphone (Nexus 4). With Runtastic, I only get a graph, as well as the average and maximum heart rate during the logged "activity". The curve on the graph only includes snapshots every 2-3 minutes (it's possible to read them by hovering the mouse on the graph, in the Runtastic website). Here is the comparison Fitbit vs. Runtastic:

During the second night (December 21, 2013), I used the BLE Heart Rate Monitor app, also for Android. That app didn't create a graph, but I could export the raw data as a CSV file (I had to purchase a Premium in-app feature for that), which I could import in Excel in order to create my own graph (see below). The CSV file included almost second-by-second data (23,800 HR values in total!), so it provides much more detailed data than Runtastic. I was also able to add a linear trendline in Excel (a similar trend can be observed on the Runtastic graph). Here is the comparison Fitbit vs. BLE Heart Rate Monitor:

It was interesting to see that even when sleeping, the "resting" heart rate is not a flat curve, there's quite a lot of variation. Has any of you performed similar experiments?

[Kapalua]

Hi Dominique,

Thanks for posting all that information. Is the BLE Heart Rate Monitor app used with any BLE HR monitor such as the Polar H7?

I would never have anticipated such HR variability while we sleep. Either that or you have great dreams!

As always, I look forward to your response.

[Dominique]

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Kapalua wrote:Thanks for posting all that information. Is the BLE Heart Rate Monitor app used with any BLE HR monitor such as the Polar H7?

I would never have anticipated such HR variability while we sleep. Either that or you have great dreams!

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 Yes, the BLE Heart Rate Monitor app does work with the Polar H7, and I assume it would work with any other BLE compatible HR sensor.

The app actually calculates heart rate variability (HRV), which I didn't know. I thought the SweetBeat app for iOS was the only one with support for HRV. The HRV value appears as one column in the CSV output by the BLE Heart Rate Monitor app. I haven't figured out how to interpret HRV yet.

Do tell us what kind of results you get if you manage to log your HR during an entire night's sleep!