VO2max, Calories, Steps and SpO2: How Accurate Are Wearables, and Why Cross-Device Normalization Matters
Steps are usually in the right ballpark. VO2max estimates can be off by several points for any one person. Calorie...
Apple Watch vs Garmin vs Oura vs Whoop: How Accurate Are Heart Rate and HRV?
Most modern wearables get resting heart rate close to an ECG. The trouble starts when you exercise hard, and especially...
