Oura introduces Cardio Effort and VO2 Max for Gen3 smart rings

What the new metrics track

Cardio Effort quantifies how much a workout taxes the cardiovascular system by combining intensity and duration. Unlike traditional metrics that focus on heart rate zones or session length, Cardio Effort allows users to compare the impact of a short, high-intensity workout against a longer, moderate session. The feature aggregates data weekly and assigns one of five personalized categories: Light, Fair, Maintaining, Building, or Reaching—each reflecting the user’s cumulative cardiovascular load.

The VO2 Max estimation feature measures aerobic fitness by calculating the body’s maximum oxygen uptake during exercise. Previously, Oura required users to complete a six-minute walking test to estimate this metric. Now, the process is passive: after at least five GPS-enabled workouts, the ring automatically generates a VO2 Max score. This update aligns Oura with competitors like Garmin and Apple, which already offer similar passive tracking. The feature is accessible through Oura Labs, the company’s experimental platform for new functionalities.

Competitive landscape

Oura’s update arrives as the smart ring market faces growing competition. Rivals like RingConn and Ultrahuman are expanding their own health metrics, while established players like Apple Watch and Fitbit already offer VO2 Max and advanced cardio tracking. Oura’s ability to deliver these metrics in a ring form factor—which prioritizes comfort and aesthetics—could attract users dissatisfied with bulkier wearables.

The launch also follows Oura’s delayed IPO, originally planned for September 2026. With the company now emphasizing product innovation, these features may serve as a proof point for long-term growth amid market uncertainty. However, Oura faces challenges, including a proposed lawsuit over accuracy claims and competition from Signal Ring, which claims to offer blood pressure monitoring without calibration—a feature Oura has patented but not yet released.

What this means

Lazyfounder analysis — our interpretation, not reported fact.

Oura’s update underscores a growing trend in wearables: form factor is no longer a limitation for advanced health tracking. By introducing passive VO2 Max estimation and Cardio Effort, Oura is directly challenging smartwatches from Apple, Garmin, and Fitbit—devices that dominate fitness metrics but often prioritize screen real estate over wearability. For founders and operators, this move highlights three opportunities:

1. Differentiation through algorithms: Oura’s shift to passive VO2 Max tracking shows that hardware alone isn’t enough—software-driven insights can create competitive advantages, especially for smaller players.

2. Niche markets matter: The smart ring category proves there’s demand for devices that prioritize comfort and aesthetics. Founders should consider whether their product’s form factor aligns with user lifestyles, not just feature lists.

3. Pre-IPO product pushes: Oura’s delayed IPO (postponed to 2026) suggests the company is focused on proving long-term value. For startups eyeing public markets, this is a reminder that product momentum can outweigh short-term financials when courting investors.

Competitors like RingConn and Ultrahuman will likely respond with similar updates, accelerating innovation in the smart ring space.

Key takeaways

• Oura’s new metrics close the feature gap between smart rings and smartwatches, particularly for fitness tracking.
• Passive VO2 Max estimation reduces user friction, aligning Oura with competitors like Garmin and Apple who already offer this convenience.
• Competitors like RingConn and Ultrahuman are likely to respond with similar updates, accelerating innovation in the smart ring category.
• Oura’s focus on product updates amid a delayed IPO suggests product momentum may outweigh short-term financials for startups eyeing public markets.

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