The Oura Ring has become a popular wearable device for tracking health and fitness data like sleep, activity, and readiness. One of the metrics it provides is an estimate of calories burned throughout the day. But how accurate is the Oura Ring at measuring calories burned? Let’s take a closer look.
How Oura Ring estimates calories burned
The Oura Ring uses proprietary algorithms to estimate the number of calories you burn each day. It does this by taking into account your personal stats like age, gender, height, and weight, along with the activity data it collects from its sensors.
The ring contains an infrared LED and an infrared sensor to detect blood volume pulse from the capillaries in your finger. It uses this data to estimate your heart rate. By tracking your heart rate along with body movement from the ring’s 3D accelerometer and gyroscope, Oura determines periods when you are active vs. inactive.
Oura combines your heart rate data with the intensity and duration of your activities. It knows that higher heart rates and intense exercise burn more calories. So if you go for a high intensity bike ride, it will calculate a higher calorie burn than during a leisurely walk. Oura also factors in your basal metabolic rate (BMR) and calories burned through normal daily activity and fidgeting.
Studies on accuracy for calories burned
Very few studies have specifically looked at the accuracy of Oura Ring for energy expenditure tracking. But some initial research is promising:
- A 2020 study published in Scientific Reports tested the Oura Ring’s ability to estimate calories burned against a portable metabolic analyzer during intense exercise. Across 8 subjects, the Oura had a mean absolute error of just 27 calories per hour during cycling periods.
- Another 2020 study in Frontiers in Physiology had subjects wear both Oura Rings and ActiGraph devices during free-living conditions for up to 34 days. The Oura closely matched the ActiGraph for estimating active energy expenditure, being within 11% on average.
The ActiGraph activity monitor has been validated against gold standards like doubly labeled water for measuring calories burned. The close comparison in this study suggests the Oura Ring provides reasonable accuracy too.
Factors that affect accuracy
While the initial research is positive, there are several factors that can affect the accuracy of the Oura Ring for energy expenditure tracking:
- Inaccurate user data – The algorithm relies heavily on the personal stats you provide in the app like height, weight, age and gender. Being off even slightly on these can throw off calorie burn estimates.
- Non-wear time – The ring can’t track what it can’t see. Removing the ring, even for short periods, leads to missed calorie burn data.
- Static activities – The Oura sensor is less accurate for estimating calories burned during low intensity activities like sitting, standing, driving, weight lifting, etc.
- High intensity training – Very strenuous exercise can push the limits of the ring’s heart rate tracking capabilities.
- Arm swinging – Activities like running where your arms swing more can overestimate calorie burn. The motion tricks the accelerometer.
The ring also won’t pick up extra calories burned after exercise from excess post-exercise oxygen consumption (EPOC). Overall, it provides an estimate, but it may be off by 20-30% or more depending on the activity.
Does Oura provide better accuracy than other devices?
Many wearables and mobile apps provide calorie burn estimates these days. Is Oura any better than a Fitbit, Apple Watch, MyFitnessPal, etc? There isn’t extensive comparative data yet, but some initial findings:
- The 2020 Scientific Reports study mentioned above also compared Oura to Apple Watch during cycling. Oura had lower error rates vs. a metabolic analyzer.
- A 2021 study in JMIR Mhealth and Uhealth compared seven wearables including Oura and Apple Watch for tracking steps, calories, sleep and heart rate against a clinical-grade ActiGraph device during a 24 hour period. For calories, Oura had lower error rates than Apple Watch.
The walking and running algorithms from Fitbit and Apple Watch are likely more refined as those brands have invested heavily in that specific use case. But for 24/7 calorie burn tracking, early indications are that Oura may provide better accuracy thanks to its unique sensors and approach.
Should you rely on Oura calorie estimates?
The Oura Ring provides a rough estimate of how many calories you burn each day. But with the potential for inaccuracy based on type of activity, it may be smart not to over-emphasize the absolute numbers it provides.
However, for relative comparisons the data can still be useful. You can leverage Oura’s calorie estimates to:
- Track trends and patterns in calorie burn over weeks and months
- Compare days when you are more active vs. inactive
- See the impact of changes like increasing your exercise
Oura’s calorie burn insights are best viewed as a guide rather than the absolute truth. Take the data with a grain of salt, but use it to understand your general activity levels and make positive daily movement choices.
How to improve accuracy
If you do want to get the most precise calorie burn estimates possible from your Oura Ring, consider these tips:
- Provide accurate profile information – Double check height, weight, age, gender and make any needed corrections.
- Wear it 24/7 – Keep it on during sleep and swimming for full data.
- Minimize arm swinging – Treadmill over running outside, elliptical over cycling.
- Enter activities – Log workouts in the Oura app for more data.
- Don’t obsess over exact number – Focus on trends and not absolute accuracy.
With smart use, the Oura Ring can provide valuable insights into calories burned and activity levels.
The bottom line on Oura Ring’s calorie tracking
So in summary, is Oura accurate for calories burned? Here are the key takeaways:
- Early validation studies show decent accuracy, especially for 24/7 estimates.
- However, accuracy depends heavily on the type, duration, and intensity of activity.
- Comparisons suggest potential improvements over other consumer wearables.
- But the absolute calorie numbers should still be considered rough estimates.
- For best results, calibrate the algorithm with your stats, wear 24/7, and track trends vs. daily numbers.
While not perfect, the Oura Ring provides some of the best calorie expenditure estimates available in a consumer wearable. It gives useful insight into activity levels when viewed from a broader perspective.
Focus on the trends and not the absolutes, leverage Oura’s calorie tracking as an awareness tool, and it can help motivate smarter daily health and fitness habits.
| Pros | Cons |
|---|---|
| Decent accuracy in studies | Less accurate for low intensity activities |
| Better than other wearables | Can overestimate with arm swinging |
| Useful for trends and patterns | Doesn’t capture EPOC effect |
| Motivates activity | Potentially large errors day-to-day |
Frequently asked questions
Does Oura track calories burned swimming?
Yes, the waterproof Oura ring will track calories burned while swimming by monitoring your heart rate and lap swimming intensity. However, the estimate may be less accurate than for dry land activities.
Can Oura tell difference between strength training and cardio?
Oura can roughly differentiate between cardiovascular exercise and weight lifting or strength training. Cardio exercise results in elevated heart rate and movement, while strength training is mostly static. However, logging specific workout types can improve accuracy.
Is Oura better than MyFitnessPal for calories?
Oura provides passive calorie burn tracking from your movements while MyFitnessPal relies on user food logging. Oura captures more complete data, but can have errors in estimates. MyFitnessPal is typically used in combination with activity trackers.
Does Oura heart rate sensor work during exercise?
Yes, the Oura ring uses a PPG optical heart rate monitor that functions during exercise. However, very high intensity exercise above 180bpm can challenge the sensor and impact calorie burn accuracy.
Can I export Oura calorie data to Apple Health?
Oura syncs its activity and calorie burn data to Apple Health. Open the Health app, go to Sources > Oura > Calories to view the exported calorie burn information.
Conclusion
The Oura Ring provides estimates of your daily calorie expenditure using heart rate and movement data. Research indicates it’s one of the more accurate options among consumer wearables.
However, the absolute numbers are still estimates and certain types of exercise can impact precision. View Oura’s calorie tracking as an awareness tool rather than a daily calorie counter.
Focus on long-term trends and patterns in the data for lifestyle insights. And leverage Oura’s calorie burn tracking to motivate healthier daily movement and behaviors.
