- Cardio Effort shows how much strain a single workout placed on the heart and blood vessels. It adds up scores weekly and compares them with each user's usual baseline. The company said it considers both exercise duration and intensity, so short hard workouts and long light workouts can receive similar scores.
- Weekly Cardio Effort is divided into five levels: Light, Fair, Maintaining, Building, and Reaching. According to the company, heart rate elevation is measured against each user's long-term resting heart rate, not an estimate of maximum heart rate.
- VO2 max is a fitness metric showing how well the heart, lungs, and muscles deliver and use oxygen during exercise. Previously it required a lab test or a 6-minute walk test, but according to the source it can now be estimated from workouts with GPS records without a separate test. The first estimate appears after completing 5 qualifying workouts.
- VO2 max is first available to Oura Labs members with Gen3 and later rings. Oura Labs is the space where the company tests experimental features. The source says Cardio Effort is rolling out to Oura Ring Gen3 and later models.
O: This may be useful for users who have used an Oura Ring for Gen3 or more and want to check their weekly exercise load. Instead of exercise time, they can check whether their weekly Cardio Effort levels leaned toward Building or Reaching.
X: You should confirm that both Cardio Effort and VO2 max are for devices Gen3 or later, and that VO2 max is first offered through Oura Labs, an experimental feature.