Ten thousand steps a day feels like a law of nature, but it began as the name of a Japanese pedometer sold in 1965: the manpo-kei, literally the "10,000-step meter". This animated explainer follows that number from a 1960s sales idea to millions of wrists, then looks at what large step studies actually found.

Chapters:

0:00 Intro

0:23 The magic number

1:19 Tokyo, 1964

2:13 The 10,000-step meter

3:19 Going global

4:21 The first big test

5:26 The curve that flattens

6:37 More is still fine

7:41 How you walk

8:32 Your number

• English AI voiceover with original synthesized music and sound effects, mixed to -14 LUFS

• Original vector animation in a flat neon style, 1080p at 60 fps

• Fact-checked, with studies cited on screen: Lee et al. (JAMA Internal Medicine, 2019), Paluch et al. (The Lancet Public Health, 2022), Ding et al. (The Lancet Public Health, 2025), Althoff et al. (Nature, 2017) and the WHO's 2020 activity guidelines

• Clearly notes where the evidence is limited (observational studies show links, not proof of cause), and ends with a reminder that it is not medical advice

The takeaway: more movement helps, the benefit curve flattens, and the most valuable steps are the next thousand.