Source: Physiologically Speaking
Consumer fitness wearables routinely misestimate VO2 max and other cardinal training metrics by margins that can misdirect training decisions, yet users treat these readings as gospel because they're quantified and continuous. The gap between what devices claim to measure and what they actually measure—compounded by individual physiological variance that algorithms can't capture—means that millions of people optimizing their training based on wearable data may be chasing phantom signals. This matters because the entire logic of the connected fitness economy depends on trust in those numbers; when the hardware is systematically off, the downstream coaching, AI recommendations, and health claims built on top lose their foundation.