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What ‘just go for a walk’ leaves out
The evidence on exercise and depression is weaker than the headlines and more interesting than the sceptics allow. It points at structure and supervision, not walks.
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Tech
The four-day week trials mostly didn’t test a four-day week
The pilots cut about four hours a week, not eight. Iceland never ran one. And the best-instrumented trial found healthier workers, unchanged revenue, and a significantly faster pace of work.
Health
The eight-glasses rule is a sentence someone deleted
The 1945 document blamed for the rule said most of your water comes from food and that thirst is an adequate guide. Both sentences were cut. Here is what the evidence actually shows.
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The sleep chart everyone copies has a footnote nobody reads
The age-by-age sleep chart is a compromise document, and the panels that wrote it said so. What the primary sources actually show about how much sleep you need.
No health authority has ever recommended 10,000 steps
Every official physical activity guideline is written in minutes, not steps. A 1965 pedometer brand name filled the gap — and it is aimed at exactly the wrong people.
The four-day week trials mostly didn’t test a four-day week
The pilots cut about four hours a week, not eight. Iceland never ran one. And the best-instrumented trial found healthier workers, unchanged revenue, and a significantly faster pace of work.
The 21-day habit rule came from a plastic surgeon’s book preface
Maxwell Maltz was describing how long patients took to get used to a new face. When researchers finally measured habit formation, the range ran from 18 days to 254.
Sport news
The four-day week trials mostly didn’t test a four-day week
The pilots cut about four hours a week, not eight. Iceland never ran one. And the best-instrumented trial found healthier workers, unchanged revenue, and a significantly faster pace of work.
Where the three-to-six-month emergency fund rule actually came from
The most repeated number in personal finance was set in 1996 by polling 156 advisers. Six million households of bank data suggest a very different answer.
No health authority has ever recommended 10,000 steps
Every official physical activity guideline is written in minutes, not steps. A 1965 pedometer brand name filled the gap — and it is aimed at exactly the wrong people.
The 21-day habit rule came from a plastic surgeon’s book preface
Maxwell Maltz was describing how long patients took to get used to a new face. When researchers finally measured habit formation, the range ran from 18 days to 254.
What ‘just go for a walk’ leaves out
The evidence on exercise and depression is weaker than the headlines and more interesting than the sceptics allow. It points at structure and supervision, not walks.
Recipes
The eight-glasses rule is a sentence someone deleted
The 1945 document blamed for the rule said most of your water comes from food and that thirst is an adequate guide. Both sentences were cut. Here is what the evidence actually shows.




































