Are wearables legit? We stress-tested the best fitness trackers and had an expert weigh in

Fitness trackers have moved from niche biohacking tools to mainstream accessories, with brands such as Oura, Garmin, Apple, and Samsung competing alongside newer entrants. The article notes that about a third of Americans use some form of wearable, while public debate has continued after Robert F. Kennedy Jr. suggested that every American should wear one. It profiles a cardiologist and biohacker, Gary Brecka of Ultimate Human, who argues the main value is not the data itself but how it changes behavior by identifying patterns in physiology and recovery. The report also says top devices can monitor metrics including heart rate, sleep cycles, stress levels, and blood oxygen, with some features extending to glucose-related predictions and menstrual-cycle estimates. It begins its review of 2026 models by highlighting the Oura Ring 5, stating the company claims the fifth-generation ring is 40% smaller than earlier versions while maintaining health-tracking performance.