Taking between 9000 and 10,000 steps per day appears to reduce the risk of an early death or heart-related event, adding legitimacy to an idea that has been criticised as unscientific.

The exact origin of the commonly held belief that people should aim for 10,000 steps a day is unclear, but it has been linked to a marketing campaign promoting pedometers in Japan.

Now, a study by Matthew Ahmadi at the University of Sydney, Australia, and his colleagues suggests the figure could hold some merit.

The team analysed more than 72,000 participants, with an average age of 61, in the UK Biobank study as they wore a movement-tracking accelerometer on their wrists for one week. “We were able to quantify daily steps,” says Ahmadi.

The participants were then tracked for an average of just under seven years, during which time 1633 people died and 6190 heart disease-related events occurred. After adjusting for other factors that could influence the risk of illness or death over that period – such as diet quality, smoking status and doing other forms of exercise – the researchers calculated that the optimal number of steps per day appears to be between 9000 and 10,000, with the benefits then starting to tail off.

Doing so was linked to a 39 per cent lower risk of dying during the follow-up period and a 21 per cent lower risk of a heart-related incident.

“This paper helps the field take a great stride forward, pardon the pun, in refining the science that underpins physical activity and sedentary time guidelines,” says Dale Esliger at Loughborough University in the UK. “It does appear to support the notion that the originally non-evidence based 10,000 steps target may indeed be about right.”

However, while Nicolas Berger at Teesside University in the UK says the study was “extremely well designed” with “rigorous methods and statistical analysis”, Esliger says wrist-worn accelerometers aren’t always the best indicator of step count.

The researchers also didn’t consider the number of steps taken per minute. “It may be that around 6000 steps performed at a higher cadence may be just as health protective as 10,000 slower steps,” says Esliger.

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