Smart watches monitor your health
I’ve long been conscious about health and fitness, but in the midst of a global health crisis, staying healthy has become a bit of an obsession. In many ways, that’s a good thing, but thinking about your health can be a double-edged sword if it winds up causing anxiety which, ironically, can negatively impact your health.
I say this because, for the past couple of weeks, I’ve been testing out smartwatches and other devices that provide useful data as well as potential reasons to worry.
There are many available smart watches and fitness bands ranging from under $30 to well over $1,000. The best-selling of these is the Apple Watch, which starts at $199 for the older Series 3 with the more advanced Series 6 starting at $399. There are plenty of reviews of Apple Watches and most of the ones I’ve read rave about them. I was impressed when I tested the Series 4 Apple watch back in 2018 when they first introduced the ability to do an on-the-wrist electrocardiogram (abbreviated as ECG or EKG), though it caused me some unnecessary stress when it gave me a false reading that could have (but didn’t) point to a problem with my heart. The new Series 6 also has ECG. Apple Watch Series 3 and SE don’t have ECG but they do notify you of high and low heart rate and irregular heart rhythm.
The Apple Watch Series 6 also tracks your blood oxygen — a measurement commonly referred to as Spo2 or oxygen saturation. Spo2 has become increasingly important since the advent of COVID-19 because a low Spo2 can be an indication of respiratory problems associated with COVID. But, getting back to the issue of health anxiety — there are plenty of other reasons why an Spo2 could fall below normal levels, according to the Mayo Clinic (tinyurl.com/spo2causes).
The Apple Watch pretty much requires you to have an iPhone. You’ll need to look elsewhere if you’re an Android user.
You don’t need a watch or to spend a lot of money to track Spo2. You can measure it with a fingertip pulse oximeter that start at under $16. I spent $18 for the Zacurate 500BL Fingertip Pulse Oximeter Blood Oxygen Saturation Monitor, which is very easy to use and — as far as I can tell — accurate. I brought it with me to a doctor’s appointment and its measure was very close to what the nurse recorded on her device.
You also don’t need a watch to measure your own ECG. The $84 Kardia Mobile Personal EKG is a small (6.3 x 3.54 x 1.18 inches; 0.6 Ounces) pocketable device that is FDA approved for EKG, atrial fibrillation, Bradycardia (slow heart rate), Tachycardia (fast rate) and normal heart rhythm in 30 seconds. The device pairs with your smartphone which displays and stores the results and allows you to email results to your doctor or — for about $25 — have it analyzed by a board-certified cardiologist affiliated with the company.
You also don’t need a watch to measure footsteps. Both Android’s Google Fit and the iPhone Health apps will do that quite well.
Still, I decided to do a deeper dive into my own health and fitness data by checking out some smartwatches that work with both Android and iOs.
I began by spending $49.99 for the Amazfit Bip U Health Fitness Smartwatch, which I wore for several days. This watch — which looks a little like an Apple Watch — is both attractive and functional with the ability to measure heart rate and Spo2 along with breathing patterns, stress levels, and “quality of sleep.” It also has “women’s health tracking,” which tracks menstrual cycles. Like all fitness bands, it also measures your footsteps and there are settings to have it measure numerous indoor and outdoor exercise routines including an elliptical, treadmill, indoor cycle and Yoga. It mostly measures duration, heartbeat while exercising, and estimated calorie consumption.
It also estimates your sleep quality by giving you a numerical score and reporting on your total amount of sleep along with the amount of deep sleep, light sleep, REM and time awake. The Tempur-pedic bed I sleep on (a subject for a future column) is equipped with the highly reliable Sleeptracker AI sensing technology whose report was relatively close to the data reported by the watch. Tempur-pedic SleepTracker has a number of other features, including detecting and responding to snoring and doesn’t require you to wear anything because the sensors are built into the bed.
The Amazafit Spo2 test is on-demand but requires you to be very still while you’re taking it. For me, it failed as often as it worked, but when it worked, the results were very close to what I got with my dedicated oximeter.
I also compared its heartbeat measurement with other devices including the oximeter and my blood pressure cuff (which also measures pulse) and taking my pulse with my finger. For the most part it was close to other measurements, although, like other smartwatches, it was sometimes off by a few beats per minute.
False heart rate alarms
For the most part, this inexpensive watch was giving me what I believe to be reasonably accurate heart rate data but occasionally it would show a very high heart rate even when I wasn’t exercising. Like other watches, you can set an alert for low and high heart rate, and a couple of times, I got an alert that my heart was beating at 120 beats per minute (more than twice my resting pulse) while sitting at my desk or watching TV. I was even awakened by the alert one night during sleep. I didn’t have any other symptoms, and when I used the watch to get a heart rate on demand a moment later, it was close to my normal rate. But I can be a worry wort and became anxious about these occasional peaks. Anxiety causes its own heart issues, so, I decided to compare the results from this inexpensive watch with those of higher-end models and got both a Samsung Active 2 Watch and a Fitbit Versa 3 — both highly rated smartwatches that start at about $200.
The good news for me (but not for Amazafit) is that when I wore the Amazafit on one arm and either the Samsung or Fitbit on the other, the more expensive watch never reported an unexpected high heart rate even when the Amazafit did and, for that reason alone, I’ve decided to stop wearing the Amazafit. It’s still a good value if you can ignore or don’t experience this one occasional flaw.
As per the Fitbit — so far so good. It doesn’t have nearly the number of features or app ecosystem of the Apple Watch, but it’s affordable and seems to be pretty accurate. It doesn’t let you measure your Spo2 on demand, but it does measure it while you’re sleeping (along with other sleep data) giving you the range of your Spo2 and an overnight average. I’d prefer it let you measure on demand but that $17 oximeter does the job. It doesn’t measure ECG but Fitbit’s $278 Sense model does. I do worry that Google plans to acquire Fitbit and will have all of this highly personal health data along with all the other data it has about us, though the European Commission last week approved the acquisition with privacy concessions from Google.
The Samsung Active 2, in theory, has an impressive array of features including fall detection, Spo2, ECG and even blood pressure, but although some of its features worked with my non-Samsung Android phone, many of the advanced features require a Samsung phone or the willingness and ability to use some third party hacks which I didn’t test.
So, now that I have all this health technology on my wrist and my phone, there’s only more thing I need to do and that’s to relax and lower my anxiety which, ironically, means spending more time enjoying life and less time looking at the data from the watch I’m wearing.
Larry Magid is a tech journalist and internet safety activist.