Nov 17, 1999

Wondering if you know how many runners there are on earth now? I'm writing a paper on running and thought to ask you. (Ken Lee, San Francisco, California)

REPLY: The wiseguy answer would be six billion. Everyone is born with the ability to run, though of course most never do -- and some can't -- after childhood.

The best numbers I can give you are from this country. About one in a hundred (25 million) Americans claim to do "some" running. About one in a hundred (2.5 million) from the U.S. population enters an organized event. About one in a thousand (a quarter-million) runs a marathon.

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