THE marathon is coming home this weekend. No athletics event is more rich in legend, but most of that has been penned since Spyros Louis won the inaugural Olympic title in 1896, and now, for the first time since, a global title is to be decided over the course made famous by him, and by Pheidippedes' mythical run.

Pheidippedes did not die gasping: ''Rejoice, we conquer,'' having run the 22 miles from the plains of Marathon, scene of the Athenian victory over a much larger Persian force in 490BC.

The battle certainly took place, but the run is a myth, crafted by Baron Pierre de Coubertin to sell the Olympic idea to the Greeks and help transmute his fantasy into reality 101 years ago.

The fable was based on a factual and more remarkable feat. According to Herrodotus, a man, almost certainly Pheidippedes, ran the 136 miles over the mountains, attempting to enlist the Spartans' help for the forthcoming battle against the Persians - and then ran back again.

It is even suggested he subsequently marched the 22 miles to Marathon and fought in a battle that helped preserve European culture against the east.

All of which might lead you to think those running in the world championship women's and men's marathon today and tomorrow are a mite soft in tackling a mere 26 miles 385 yards.

The event, for the first time, doubles as the World Cup team championship, and participants will observe tradition by carrying an olive twig to be discarded on the mound where the Athenians buried their slain.

Television has now replaced Herrodotos to tell future generations, but one participant has strayed to the wrong side of the camera.

Angharad Mair is one of the four-strong British women's team this morning, foresaking a day job with the BBC Wales language channel as a newsreader and sports magazine presenter with Tocyn Tymor (Season Ticket).

Until six years ago, her personal sporting horizons did not extend beyond a hockey pitch. When she applied for the post, the interviewer asked for off-beat ideas. ''I told them I was about to run a marathon - that was mainly to keep in shape, because I was about to be 30.''

She landed the job, but her bluff was called. She had to make a magazine programme round her own efforts in the 1991 New York Marathon. As Liz McColgan won on her debut, Mair was making hers in 3hr 29min, 62 minutes behind the Scot. Now, just five marathons later, Mair is in the British vest that McColgan declined.

She is so high profile that she is pursued on training runs by children seeking her autograph, and was even accosted on the start line at the national cross-country championships.

''I get lots of letters from old ladies, saying I look awful thin - we worry about you.''

Her schedule is regularly 80 hours a week, and fitting in training often means running immediately after coming off air, face hidden by a baseball cap: ''Full glam make-up, but if I get back late, after reading the news, I am not going to bother taking it all off,'' she said.

She confesses running is ''a drug, really. When it is hard to fit everything in, and I think: God, why am I doing this, I think about so many highlights of my life, and remember that they have come from running.''

Her mother, staunchly Welsh chapel, is somewhat disapproving of a her daughter running through the streets in underwear. ''My mother is horrified.

''She worries about the stresses of marathon running, and I don't think she believes it is the kind of thing a 36-year-old woman should be doing.''

She has taken a seven-week break from television to prepare, spending time in the French Alps, at Font Romeu with Bruce Tulloh, coach of Richard Nerurkar, the leading British men's hope who yesterday ruled himself out with a viral problem. This leaves Britain unable to complete a team in the cup.

During Mair's preparations, on three successive mornings she ran the last 18 miles to the finish in the 1896 Pana- thinaikon stadium.

''I got a taxi to drive me to the outskirts. When I got out to run back, the driver would not leave - he thought I was mad.''

She knows she has no hope of a medal, and the enormity of the task in the forecast 40-degree heat can be judged by the fact the course record of 2-11-07 has stood to Britain's Bill Adcocks since April 1969, when he won the annual Spyros Louis memorial event.

''I got a medal and a trophy,'' he recalled yesterday. ''Nothing like the $60,000 first prize now. They didn't give money to madmen, which is how we were regarded. Even the rest of the British team treated you like nutters.''

Adcocks was forced to drop out when the European championships were held on the course later that year, the title being won by England's Ron Hill, with Jim Alder third.

Even Clydebank-born Alder, 1966 Commonwealth cham-pion for Scotland in Jamaica, and one one of the hardest men ever to pull on a British vest, recalls the course as fearsome.

''A nine-mile climb from the plain of Marathon from 10 miles onwards, then a stunning panorama of Athens, with a helipcopter overhead, blowing dust in our faces,'' he said.

There was no cosseted full-time training for him, but 100 miles per week after 10-hour days as a bricklayer.

He believes the current generation is pampered, and the number of international marathon successes achieved in recent years by hungry fighters from altitude peasant communities of Mexico, Spain, Portugal, Ethiopia, Korea, and Kenya would seem to support his theory.

''I remember the race clearly - September 13, because my wife, Cathleen, was giving birth to our daughter, Susan,'' said Alder.

''Whenever I trained, I got loud cheers from the farm workers. I wondered why I was so popular, until I dis- covered my blue-and-white Morpeth vest was the same as the Greek national colours. I became known as Jimmy the Greek.

''I only just hung on for third, in about 2-18. I'm not surprised Bill's time is still the record - and I doubt if anyone will beat that this weekend, either.''