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The popular target of 10,000 steps a day comes from a Japanese step counter sold in the mid-1960s as the manpo-kei, meaning '10,000-step meter'. It was a catchy goal, not a threshold set by clinical research.

Manpo-kei history; modern step-count epidemiology

HealthScience

The story behind the card

In 1963, ahead of the Tokyo Olympics, Iwao Ohya, head of a large Tokyo clinic, told engineer Juri Kato of the clock and meter maker Yamasa that Japanese people were moving too little and should walk 10,000 steps a day. Two years later Kato's manpo-kei went on sale, and walking clubs soon formed in all 47 of Japan's prefectures. The figure spread abroad through marketing rather than research. A 2025 review of dozens of studies found that about 7,000 steps a day was linked with much of the benefit for the risk of death and disease, with smaller gains beyond that for most outcomes.

Türkçe oku
Günde 10.000 adım hedefi, 1960'ların ortasında Japonya'da satılan ve adı “10.000 adım ölçer” anlamına gelen manpo-kei adlı adımsayardan gelir. Bu sayı klinik araştırmalarla bulunmuş bir sağlık eşiği değil, akılda kalsın diye seçilmiş bir hedefti.

1964 Tokyo Olimpiyatları öncesinde, 1963'te, Tokyo'nun büyük kliniklerinden birini yöneten Iwao Ohya, saat ve ölçü aleti üreticisi Yamasa'dan mühendis Juri Kato'ya Japonların çok az hareket ettiğini, herkesin günde 10.000 adım yürümesi gerektiğini söyledi. İki yıl sonra Kato'nun manpo-kei'si satışa çıktı; kısa sürede Japonya'nın 47 ilinin hepsinde yürüyüş kulüpleri kuruldu. Sayı dünyaya araştırmalarla değil, pazarlamayla yayıldı. 2025'te onlarca çalışmayı bir araya getiren bir derleme, günde yaklaşık 7.000 adımın ölüm ve hastalık riskindeki yararın büyük kısmını sağladığını, bundan sonrasının çoğu sonuç için daha az şey kattığını buldu.

Sources and further reading

Background reading: Pedometer
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