The VO₂ Accuracy of Wearables | Peter Attia

Not SupportedWrist-based optical heart rate monitors used by most wearables are inaccurate and their readings can drift significantly.

Partially SupportedWearables often estimate VO2 max automatically from general workout data rather than allowing users to initiate a true test, which can lead to inaccurate readings, especially if a user primarily does Zone 2 training.

Partially SupportedWearable devices estimate VO2 max using algorithms that infer gas exchange from heart rate, pace, power, age, sex, and weight, rather than directly measuring it.

Not SupportedVO2 max estimates from wearable devices can have significant swings and should not be relied upon solely.