Wearable fitness trackers show promise for health monitoring, but experts caution limits

Five popular consumer fitness trackers were worn by Daily Mail reporters for a month to test how well they track sleep, steps, heart health and pace of aging. The devices tested were Fitbit Charge 6, Garmin vivoactive 6, Apple Watch Series 10, Whoop MG device with Life membership, and Oura Ring 4. The testers looked at daily step counts, sleep quality, heart rate variability and whether each device could offer personalized advice to improve health. The results highlighted the varied performance across brands and suggested wearables may motivate users to adopt healthier habits, though experts warned that no single device should be treated as a medical diagnostic tool.

Health experts say wearables can encourage more activity and better sleep, which may help manage blood pressure and diabetes and could influence dementia risk research. A 2025 study found that wearable derived metrics, particularly walking data, were associated with dementia risk profiles. Specifically, for every 4.6 centimeters per second increase in gait speed, dementia risk decreased by about 32 percent; for every 3,200 additional steps walked, risk fell roughly 30 percent. By contrast, sleeping more than nine hours was associated with a 50 percent higher odds of a dementia diagnosis, and an early bedtime before 9 p.m. raised risk by about 60 percent compared with a normal bedtime. Dr Barry Hahn, an emergency physician and Garmin user, cautioned that while wearables can boost health, they are not a cure all for chronic disease.

During the trial, the reporters assessed step counting by comparing each device against a manual tally of 1,000 steps. Garmin, Apple Watch, Fitbit and Oura yielded averages just over 1,000 steps in three tests, while Whoop lagged behind, recording an average of 771 steps for the same 1,000 steps. Whoop says it uses the body's natural motion to estimate steps, a method that some studies show can undercount at times. The team noted that many devices set adaptive daily step goals, nudging users to move more after periods of inactivity. For instance, Garmin and Apple Watch adjusted goals based on the user's recent activity, sometimes encouraging longer walks or shorter but more frequent bursts of movement.

Besides steps, the test examined stress tracking. Oura and Whoop offered daily stress breakdowns with AI driven tips to cope with psychological strain. The reporters saw sessions where stress rose in the morning while covering deadlines or during long drives on hiking trips. The devices warned users to take mindful breaks, and the team noted this could prompt healthier habits, such as short walks or breathing exercises. Public health experts say about a quarter of Americans report high daily stress, a factor that can disrupt sleep and contribute to weight gain and chronic conditions if sustained.

On exercise, the testers put devices to the test across walking, running, swimming, weightlifting and hiking. Garmin generally performed best for running and swimming thanks to a fast start interface and a route map that highlighted pace changes; its pre programmed Couch to 5K plan was cited as helpful. Apple Watch and Fitbit were strong for walking, with automatic activity detection and early prompts after activity begins. Oura also detected activity and prompted users to confirm workouts, while Whoop offered a strain score that recalculated daily based on sleep and physiological stress markers to guide training intensity. Battery life affected some devices; Apple Watch shorter battery life limited its usefulness on longer hikes, while Whoop's motivation features were appreciated by some testers.

Sleep emerged as another key area. Over a month, Garmin, Oura and Whoop produced similar estimates of nightly sleep, averaging roughly six hours and 37 minutes, while Apple Watch tracked about seven hours and six minutes and Fitbit recorded about four hours 48 minutes. Fitbit reportedly struggled to detect sleep cycles at times, requiring manual adjustments. The testers appreciated AI sleep guidance from Whoop and Oura, including bedtime recommendations and chronotype insights that aligned with their personal routines. One tester shifted to reading before bed after a suggestion and found sleep quality improved; another adjusted lighting to evening routines based on Whoop guidance.

Gimmicks and personalization dominated the user experience. All three testers praised Whoop and Oura for AI coaching that helped plan workouts, optimize bedtimes and manage daily routines. Whoop biological age feature and frequent mental age style updates provided motivation for longer workouts, while Oura chronotype and cardiac age features offered tailored sleep and cardiovascular insights. The testers described Garmin rewards as encouraging but more utilitarian in nature. Cassidy notably preferred the Oura Ring for its discreet form factor and sleep data; Luke continued to favor Whoop for its continuous coaching, and Alexa found Garmin useful for longer hikes even if she placed less emphasis on Apple Watch due to battery life.

Verdict and implications. The testers indicated they would continue wearing their favorites, with Luke planning to keep Whoop and Garmin for swimming, Alexa sticking with Oura and Garmin for hiking, and Cassidy continuing with the Oura Ring as her primary health wearable. The piece notes that wearables can motivate healthier habits and offer insights into sleep and stress, but public health officials reiterate that devices should complement, not replace, medical care, and that users should consult professionals for diagnoses.

Context and limits. The report underscores the broad uptake of wearables, with about 40 percent of Americans already wearing one daily. It also highlights a debate about how much stock to place in wearable data for medical decisions. The 2025 dementia risk study cited in the piece points to associations rather than causation, and researchers emphasize that lifestyle factors, including regular physical activity and adequate sleep, remain central to reducing risk. The article also touches on a broader discussion of wearable adoption, including references to political calls to normalize wearables and integrate them into public health messaging, while noting that scientific interpretation of device data should remain cautious.