Polar Vantage and Oura Physical Activity and Sleep Trackers: Validation and Comparison Study

Area of Science:

• Wearable technology validation
• Physical activity and sleep monitoring
• Consumer-based sensor accuracy

Background:

• Consumer activity trackers are increasingly used in research for physical activity promotion and estimation.
• Validation studies are needed to assess the accuracy of newer consumer devices.

Purpose of the Study:

• To compare the Polar Vantage watch and Oura ring (generation 2) against research-grade instruments.
• To assess validity and comparability for physical activity, total energy expenditure, resting heart rate, and sleep duration in free-living adults.

Main Methods:

• 21 participants wore Polar Vantage watch, Oura ring, ActiGraph accelerometer, and Actiheart monitor for up to 7 days.
• Participants also completed a sleep diary.
• Analyses included correlations, Bland-Altman plots, and mean absolute percentage errors.

Main Results:

• Both devices showed strong correlations with ActiGraph for steps, moderate-to-vigorous physical activity, and total energy expenditure.
• Polar watch and Oura ring strongly correlated with sleep diary-derived sleep durations.
• Oura ring showed very strong correlation for resting heart rate; mean absolute percentage error was low for Oura's sleep duration and resting heart rate.

Conclusions:

• Oura ring may substitute Actiheart for resting heart rate measurement.
• Polar watch and Oura ring could replace sleep diaries, depending on acceptable error margins.
• Neither consumer device can replace ActiGraph for activity and energy expenditure but may serve as supplementary measures.