Visible Plus: Heart Rate Monitoring

This is an overview of heart rate monitoring using the Polar Verity Sense arm band paired with the Visible Plus app.

This is part of a longer review of the Visible Plus app.

Accuracy

I believe that this heart rate monitor is pretty accurate. There were no times that I thought, “That heart rate can’t possibly be right” like I do sometimes with a wrist-based heart monitor.

Comfort

I didn’t have any significant comfort issues wearing the arm band. I wore it both just below and just above my elbow. Polar says to wear it on your non-dominate arm, but my left shoulder is bad and when I wore it on my left arm, my shoulder got really aggravated.

Heart Rate Zones

Visible Plus has three heart rate zones:

  • Rest - up to 5% above Resting Heart Rate (73 bpm for me)
  • Exertion - up to 60% of Max Heart Rate (102 bpm for me)
  • Over Exertion - over 60% of Max Heart Rate

These zones appear to be based on research related to Chronic Fatigue Syndrome. Note that these heart rates are quite low. Sitting up in a chair and watching soccer would put me in exertion. Taking a shower puts me in over exertion.

You can change the thresholds. It’s just not clear what they should be changed to.

App Display

The heart rate and zone appear in big numbers on the first page of the app. The app updates the heart rate every second. The act of pulling out my phone and opening the app would cause a change in your heart rate and then if I held the app open, I could watch my heart rate drop. Just by changing from 72 to 73 bpm, I would go from “rest” to “exertion,” which is clearly not true biologically. I made myself a little crazy trying to “rest.”

When I went on walks, I would have to pull my phone out to see my heart rate, which is much less convenient than a fitness watch.

Alerts

In the app you can set an alert if your heart rate is in Over Exertion more than X minutes. Especially without a clear boundary for what “Over Exertion” is, that alert just made me crazy and I turned it off.

Battery

The heart monitor battery only lasts 24 hours and the app is not really designed for overnight monitoring, so that’s when I charged the monitor and my phone. This means there’s no overnight heart rate measurement.

Waterproof

The monitor is waterproof, so I wore it in the shower a couple of times to see what my heart rate did there. The stretchy fabric band got soaked. A towel would not thoroughly dry it and I didn’t want to wear wet fabric tight against my skin all day, so I would air dry it or use a hair dryer.

I don’t think regular use while taking a shower is practical, but if you are crashing after showers, this could help find solutions that keep your heart rate down.

For swimming the monitor comes with a clip to attach to your goggles. I never tried that.

Graphs

The app shows graphs of your heart rate. It’s a bar graph where white is Rest, blue is Exertion, and red is Over Exertion. (I would show the graphs, but my subscription expired and the data is no longer visible in the app.) The tall red bars make it look like I did something very dangerous. “Oh no, my heart rate went over 102!” This is really not good for anxiety. What’s worse is the estimate of 60% of max heart rate is not very accurate. I have done some work to try to find the threshold for myself, but I did not succeed.

The app does not report max heart rate. You can find it by looking through the graph and trying to pick out the tallest points with your finger, but that’s a real pain.

Disconnections

Some days the heart rate monitor would stay connected to the phone app with no problems. Other days it would disconnect frequently and I would have to close and re-open the app. Long sleeved clothing seemed to make the disconnections worse, but that could be a spurious correlation.

I also use the arm band with the Polar app and it had the same problem.

Export

The app has an export function, but it only exports the data from the morning and evening check-ins, which include resting heart rate per day. The app does not allow download of the per-minute heart rate data.

Once your subscription ends, you lose access to all the heart rate data.

Conclusion

This heart rate monitor encouraged me to rest and keep my heart rate down, but once I was out of a crash cycle, I just found it introduced too much anxiety to be useful.

Because there are not tools for analyzing the heart rate, it’s very difficult to figure out what the true threshold for Over Exertion should be.