News Every Day | Yesterday, 19:00

Larry Magid: Smart ring tracks health, fitness data with long battery life

I’ve been wearing a fitness band or a smart watch for years and have benefited from the insights into my exercise, heart rate, sleep quality and other metrics. But not everyone wants to wear a watch, especially while sleeping, so I decided to try out one of the new generation smart rings.

The obvious benefit of a ring is that it’s smaller and easier to wear 24/7, including while sleeping and exercising. But there are other advantages. I’m testing the RingConn Gen 2, which competes with the industry leading Oura Ring. Unlike the Oura ring, there are no monthly or annual subscription fees associated with Ringconn.

Unlike most smart watches, smart rings don’t have to be charged daily. The Ringconn claims 10 to 12 days battery life, which seems about right based on my usage. It’s liberating not to have to charge it every day, especially if you wear it while sleeping. I also sleep with my Pixel Watch 3, so I have to find a time during the day to charge it when I’m not relying on the watch to track my movements.

Unlike a smart watch, rings don’t have displays, so you need to open their smartphone app to view your data. I don’t find that inconvenient in most situations, though when walking or doing other exercises, it’s nice to be able to see your pulse rate and other metrics just by glancing at the watch. That’s especially true if you don’t like carrying a phone or if it’s difficult or dangerous (such as cycling) to look at your phone.

Sleep apnea detection

One reason I’m wearing the ring is to evaluate my sleep. I have sleep apnea, and even though my CPAP machine reports nightly apnea events, I like to get other metrics to verify its data. Apple has just added sleep apnea detection to its latest watch, but most personal fitness devices don’t attempt to report sleep apnea. Ringconn added that feature to its new ring. The company claims 90.7% accuracy, but the device is not FDA approved, and I am not aware of any peer reviewed studies to verify this claim. In my experience, it did measure apnea events on some nights but not on others, even though my CPAP machine did detect a few events. Anything less than five per hour is considered normal.

Although the numbers reported by my CPAP and the ring were not exactly aligned, they were close, indicating that it does seem to give a reasonable approximation of events during the nights when the feature worked.

Not for medical diagnosis

All reputable fitness device makers caution users not to rely on their devices for diagnostic purposes. You should see a medical provider if you have any reason to believe you have sleep apnea or any other medical condition. Doctors have far more accurate ways to measure apnea, but the advantage to having it on a fitness device is that you can get a sense of how you’re doing over a long period of time instead of just an occasional snapshot from a medical sleep study. The same applies to other metrics that you can take at home, including blood pressure and SPO2.

SPO2

Because of my apnea, I sometimes track my SPO2 while sleeping to know my overnight blood oxygen levels. Fitbit (which is integrated into the Google Watch) gives me a nightly average and range but doesn’t show how it goes up and down over time. Fitbit only measures SPO2 while sleeping. The Ringconn measures SPO2 throughout the day and night and shows a graph of its ups and downs over time. There is also a way to take an immediate measurement.

I’ve compared its results to a pulse oximeter and to the Wellue medical grade O2Ring Oximeter Continuous Oxygen Monitor, which can be worn all night. Again, the numbers weren’t exact, but they were close and trend in the same direction. As with other metrics, these are indicators, not diagnostic tools. Sleep Foundation recommends that “Anyone who is monitoring their blood oxygen levels should talk to their doctor about the right level for them and what level should be considered too low.”

The Ringconn app also graphs heart rate, which tracks very closely with the results from my Google Watch. It reports on its most recent reading and your current rate if you click on the measure icon. Most fitness watches don’t require you to press anything to get your current rate. It also reports average heart rate, resting rate and range.

Like many fitness trackers, the Ringconn reports heart-rate variability (HRV), which is the variation in the time interval between heartbeats. “Your heart’s variability reflects how adaptable your body can be,” according to Cleveland Clinic. “If your heart rate is highly variable, this is usually evidence that your body can adapt to many kinds of changes. People with high heart rate variability are usually less stressed and happier.”

Sleep tracking

Like most sleep trackers, the ring measures total time asleep, time in bed and sleep stages: Awake, REM, Light and Deep. It also measures respiratory rate and skin temperature.

Although sleep trackers, in general, do a pretty good job of measuring how long you sleep, they tend to be notoriously inaccurate when it comes to sleep stages. My results from Ringconn usually differ from Fitbit and my Sleeptracker app. As Johns Hopkins Medicine points out, “They often measure inactivity as a surrogate for estimating sleep. Most sleep tracking devices make some guesstimate as to how much you’re actually sleeping. … Still, tracking devices can definitely be useful for helping you recognize patterns in your sleep habits.”

The Ring’s Activity screen shows steps (very close to what Fitbit reported), calories from activities and basal metabolism calories, which are also close to what Fitbit estimated for me. It shows activity intensity ratio as percentages of inactive, low, moderate and vigorous and allows you to track outdoor and indoor running and outdoor cycling but not the larger number of activities that Fitbit and many other trackers cover.

Conclusion

Although no tracker is all encompassing and 100% accurate, the Ringconn seems to give pretty good results based on my two weeks of testing. At $299, it’s priced competitively with smart watches, though you can find Fitbit and other activity trackers for considerably less. For me, the fact that I don’t have to charge it more than weekly at most is a big selling point, and I do think that, over time, the trending information it presents will prove useful.