How Oura Measures Steps
The Oura ring registers all your daily movements and their intensities, from light housework to heavy workouts. From the gathered data, Oura’s activity algorithms are fine-tuned to recognize steps from the rest of your daily movement. Oura is able to identify step patterns within a very small window of time (30 seconds) and with a high level of precision from your finger. Any non-step movement is still captured in your total activity.
Other wearables or apps may show different step estimates because they use a different method of categorizing steps. Many trackers set a different threshold for what counts as "activity" while others categorize all movements as steps.
How Oura Measures Activity
The Oura Ring uses a 3D accelerometer for activity tracking which measures how your ring moves up and down, side to side, and back and forth. This system captures most of your daily activities well, however, all accelerometers have more difficulty with activities that involve limited hand movement in one direction (e.g, an elliptical, lifting weights), no hand movement (e.g., cycling), or intense movement that is isolated to your hands (e.g., drumming).
To improve the accuracy of your activity tracking, make sure the sensor bumps of your ring are on the palm side of your finger. For non-step-based activities that are more difficult to measure (e.g., yoga), manually adding your activities or workouts on the Home tab can improve the accuracy of your Activity Score.
How Oura Uses METs to Calculate Energy Expenditure
Oura calculates your daily energy expenditure using METs or Metabolic Equivalents. MET is a common measure used to express the energy expenditure and intensity of different physical activities. If the MET value of a specific activity is 4, it means that you’re burning 4 times as many calories as you would burn while resting.
The time you spend doing different activities with specific MET values can be expressed as MET minutes. For example:
- 30 min x brisk walking (MET value=3) = 90 MET minutes
- 30 min x jogging (MET value=7) = 210 MET minutes
One Metabolic Equivalent (MET) corresponds with Resting Metabolic Rate (RMR). RMR is the total number of calories burned while your body is completely at rest. This is part of what your body needs to sustain itself while you’re awake. Because accuracy is at the heart of how Oura provides you with personalized insights, by using 1.5 METs as the lowest threshold for activities that contribute to your daily active calorie burn, we’re able to generate a value that reflects only calories burned through physical activities—as opposed to a combination of calories burned through physical activity and those acquired through bodily maintenance that takes place while you’re at rest.
Sedentary vs. Physical Activities
During sedentary activities, METs range from 1 to 1.5. Sedentary activities include dining, or lounging while watching television. In contrast, active calories relate to intentionally active tasks or activities (e.g., household chores, walking the dog, or dancing). Physical activities typically result in calorie burn greater than 1.5 METs.
Active calories above 1.5 METs are typically associated with active energy burn. Using 1.5 METs as the threshold for active calories prevents you from accumulating large amounts of active calories from low-intensity activities. This increases the accuracy of your Activity Score, and metrics found on the Activity tab—and doesn't exaggerate calories burned while you're seated or at rest.