Oura and Polar are two wearable brands that athletes and fitness enthusiasts adore. Although they are two very different devices on the outside, in this Oura vs. Polar review, we compare the functionalities of the smart ring and smartwatch apples to apples and shed light on their tracking capabilities for heart rate, activities, sleep tracking, and recovery, which are critical to your performance. Find out which device stands out and suits your performance tracking needs.
Heart Rate Monitoring
Both Oura and Polar use an optical heart rate sensor, and although they are using the same technology, the execution is different. With its suite of green LED sensors, Oura promises a 99.6% accuracy, providing more accurate continuous heart rate tracking, especially during sleep. Even with workout and activity heart rates, Oura is pretty reliable. Polar gives random spikes in heart rate data more than Oura and for the most part, tends to record shifts in HR movements later than Oura. There were a few spikes I noticed that Polar picked up but Oura did not and eventually came back down to agree with Oura’s readings. This instance alone suggests that Oura’s readings are more accurate than Polar's.
Oura has been excelling in the sleep tracking space, which I think no other wearable maker can top so far. Among its sleep metrics include sleep duration, sleep quality, sleep latency, sleep score, and detailed sleep stages (deep sleep, REM sleep, and light sleep). And just recently, Oura added naps. So far, Oura has the best sleep monitoring functionality, vastly improving the quality of my sleep over the last two years. With Polar, you also get a detailed analysis of your nightly rest with a bunch of sleep metrics, such as sleep stages, length of sleep, and interruptions. It uses two different sleep metrics: Sleep Charge and ANS Charge. Sleep Charge is directly affected by sleep stages—sleep duration, continuity of sleep, length of interruptions, and how long was spent in light, REM, and deep sleep. ANS Charge is impacted by heart rate, HRV, and breathing during sleep. In some cases, Polar records sleep later than Oura. But other than that, Polar’s sleep tracking technology is as good as Oura’s.
Oura has pretty much all the activity metrics you need, including steps, calorie burn, training frequency and volume, recovery time, and activity score, among others. You also have the option to be notified when you’ve been static for an hour and set activity goals. The problem, however, lies in the execution of its automatic activity detection, which is hit-and-miss. Oura has a problem sensing which movements have transpired, even for basic activities like running and walking. Activity suggestions are way off a lot of times. Oura supposedly can automatically detect over 30 different movements, including surfing, yoga, biking, strength training, high-intensity interval training (HIIT), core exercises, and even household chores. Meanwhile, Polar has an automatic activity-sensing feature and a reminder feature that alerts you to take active breaks when you become idle. You also get a daily activity goal according to your activity level setting and personal data. Activity tracking is clearly not Oura’s strength. This is actually one thing I would really love Oura to focus on soon. Polar, on the other hand, hits the nail on the head with its technology.
Another functionality that has been an obsession of mine with Oura is the recovery monitoring called ‘Readiness.’ The Readiness score is entirely based on several factors, including sleep, heart rate, HRV, body temperature, and activities. So far, Oura has been consistent with the suggestions and scoring. I can only remember a few instances where I thought Oura got my recovery wrong. Polar has a couple of different recovery monitoring tools. There’s the free Nightly Recharge feature that requires no effort from you as this automatically gives you a score in the morning with ANS and sleep metrics. Note that Nightly Recharge will need at least 3 days during a 28-day period. Polar also has smart features like Recovery Pro and Training Load Pro for a more advanced and accurate read of your recovery and performance. If you are using a Polar smartwatch with the FitSpark daily training guide, FitSpark will suggest ready-made exercises designed for you according to your fitness level, training history, and recovery status.
It’s difficult to compare a smart ring and a smartwatch if we just look at the outside appearance of the two. Sure, Oura is more comfortable for sleep tracking, while Polar watches are best for monitoring activities. At the end of the day, it’s a matter of preference and the functionalities you need.
In terms of battery, Oura can last for up to 7 days. Charging time takes about 20-80 minutes. Polar watches can last for up to 4 days in watch mode with continuous heart rate monitoring and up to 50 hours in training mode with wrist-based heart rate and connected GPS.
Oura can be submerged up to 100 meters underwater. You can swim with it, shower, or even be in the hot tub or sauna with it. I used mine when cliff diving and freediving a few times, though Oura does not recommend so. Most Polar watches and fitness trackers can be used for swimming. These include A370, Grit X, Grit X Pro, Ignite, Ignite 2, M200, M400, M430, M460, M600, OH1, Pacer, Pacer Pro, Unite, V650, V800, Vantage M, Vantage M2, Vantage V, Vantage V Titan, Vantage V2, and Verity Sense. Oura’s memory can store data for up to 6 weeks offline, while most Polar smartwatches can record up to 90 hours of training data without worries.
Oura 3 is available in two different styles and five colors: silver, black, stealth black, gold, and rose gold. Price starts at $349 or €350 with an optional membership fee of $5.99 or €5.99 per month. It comes with a sizing kit.
Polar smartwatches range between €200 and €600 ($198-$595). Polar watches vary in color.
Oura vs. Polar: The Verdict
Both Oura and Polar are great sleep trackers and can be used as an alternative to a manual sleep diary. Oura can also be used to measure resting heart rate (RHR) but neither of these devices can replace an actigraph to measure steps, physical activity, and total energy expenditure. Both devices solely rely on optical heart rate sensors and make estimates based on a few factors. Nevertheless, they can be used as an extra source of physical activity measures. Between Oura and Polar, the latter wins in terms of activity tracking. In terms of heart rate tracking, Oura seems to have knocked the accuracy out of the park not because we are certain it is accurate but just by looking at the sample size and the variation of heart rate it records. Either way, take it with a grain of salt. Finally, Polar watches don’t have blood oxygen monitoring, which is surprising, considering that even cheap wearables have it. Oura 3 has blood oxygen monitoring, which really helps if your goal is to improve your sleep and recovery. If you’re solely looking for performance tracking, Polar takes the cake for its more accurate activity tracking. Nevertheless, Oura is still a great device with a robust sleep and recovery monitoring system. At the end of the day, it’s a matter of choosing which form factor you like better.