Scientists compared the clinical walking speed test with data from fitness trackers

Two ways to measure gait

An international team of researchers has found that step frequency recorded by a wearable device on the wrist gives a result close to the standard clinical walking test when assessing the risk of death. Kun.uz reports this citing a publication in the journal JAMA Network Open; the article itself is available in open access on the journal's website. The work involved researchers from the Norwegian University of Science and Technology, the French National Research Institute for Agriculture, Food and the Environment, the University of Leicester in the UK, and other European research institutions.

Why walking speed matters

Walking reflects the joint work of muscles, joints, the nervous and cardiovascular systems. With age, due to chronic diseases and declining physical endurance, the pace of movement may change, so walking speed is considered one of the indicators of the body's overall condition and is used in assessing adverse health outcomes, including the risk of death. The limitation of the clinical test is that it captures only a brief episode: a person walks a short distance in an office, and the result does not necessarily reflect their usual manner of moving in everyday life. Therefore, the researchers compared two approaches: measuring speed on a standard test and counting steps per minute in everyday life.

How the study was conducted

The analysis included 4,067 participants of the British Whitehall II project. The measurements were taken in 2012–2013; the average age of participants was 69.3 years, and 74.4% of them were men. In the clinical test, volunteers were asked to walk 2.44 meters at a normal pace, as if walking down the street on their own business; the test was repeated three times and the average speed was calculated. To assess everyday activity, participants wore an accelerometer — a device that records movements — on their wrist for nine days. Records meeting the requirements for at least one day were included in the analysis; on average, each person had 7.9 days of usable data. Based on the records, the researchers calculated, among other things, the median step frequency — the value that falls in the middle of the ordered series of recorded walking paces and reflects a person's habitual speed of movement.

Result and limitations

According to the headline of the Kun.uz report, people who walk faster had a 17% lower risk of death. The detailed specifics of this finding — which exact groups were compared, over what observation period, and with what adjustments — are not disclosed in the available summary of the publication, so the exact wording of the result should be verified against the article itself in JAMA Network Open. The main methodological confirmation from the report is this: data from a wearable device in everyday life produced a result close to the clinical assessment, making it a potentially useful tool where the standard test is unavailable or does not reflect a person's usual activity.