Buying guide: which wearable offers the most accurate heart rate and spO2 for outdoor runners?
When I go for long runs in cold, windy weather or push a tempo session up a steep trail, I want two things from my wearable: reliable heart-rate data I can trust in the moment, and SpO2 readings that actually mean something instead of being a noisy number that changes every minute. Over the years I’ve tested watches and straps in the lab and the field, and I’ve learned that the “most accurate” device depends on what you value most —...
