Myth #24 — The 10,000-Step Target Was a Pedometer's Name

Ten thousand steps a day is the number most people carry as a pass mark: clear it and the day counted, miss it and the day did not. The number has a documented origin, and that origin is a product launch.

In 1965 Yamasa Tokei Keiki, a Japanese clock and instrument company, released a consumer pedometer and named it the Manpo-kei, the ten-thousand step meter, in the years after the 1964 Tokyo Olympics. 1 I-Min Lee, an epidemiologist at Harvard Medical School, told Popular Science that no actual studies had looked at 10,000 steps when the device was developed, and that the figure was made up in the sense that 10,000 sounds good and is easy to remember. A review that chased the recommendation's spread reached the same place from the other end: 10,000 steps a day "can be traced to Japanese walking clubs and a business slogan". 2

Measured data arrived decades later. In a cohort of 16,741 women with a mean age of 72 who wore an accelerometer for a week, the women averaging about 4,400 steps a day had a 41 percent lower death rate than the women averaging about 2,700. The decline in risk leveled off at about 7,500 steps a day. Once total steps were counted, how briskly the women walked showed no clear relationship to mortality. 3

A pooled analysis of 15 cohorts, 47,471 adults and 3,013 deaths sharpened the shape: risk kept falling with more daily steps until about 6,000 to 8,000 among adults 60 and older, and until 8,000 to 10,000 among adults younger than 60. Both papers open by noting that 10,000 steps a day is widely promoted with little evidence behind it. 4

Both analyses are cohort studies: they count steps on a device and follow who dies, so what they show is what travels together with walking. The same 2004 review that traced the slogan suggested goals set against a person's own starting point instead. Your phone already reports a seven-day average. Note that number, add a thousand steps a day to it, and read it again in a month.