Half marathon runners with visible tags at the Long Island...

Half marathon runners with visible tags at the Long Island Marathon finish line are, from left, Aycan Turkmen of East Rockaway with a time of 2:02:49; Kristoffer Schnepf of Lyndon Center, Vt., 2:02:51, and Lourdes Medina of Medford, 2:02:50. (May 6, 2012) Credit: Joseph D. Sullivan

This particular human race has evolved toward Sunday's 40th anniversary. When it debuted as the Earth Day Marathon in 1973, Long Island's annual 26-mile, 385-yard test was widely considered aberrant behavior, a small knot of skinny folks running around in their underwear.

Now? Emilio Garcia, a 29-year-old from Mexico who lives in Astoria, found appreciative crowds "all the time; every mile, every mile" through his 2-hour, 36-minute, 22-second victory in the Long Island Marathon.

He was one of 6,630 souls who participated -- there were 418 in 1973 -- in what has grown into a weekend "festival of races" -- one-mile and 5-kilometer races on Saturday before Sunday's 10-kilometer, half-marathon and marathon events.

In the beginning, the course consisted of repeated loops through Eisenhower Park. In 1978, it was set loose onto the Wantagh Parkway and in recent years sent through neighborhoods of the "Nassau Hub," with street closings to accommodate the foot traffic -- that was unheard of in 1973.

Paul Fetscher -- who organized that first marathon on the Island, won it in 1976 and, at 66, ran the half Sunday -- remembered in those days people shouting sarcastically to him during his training runs, "Hup-two-three-four, hup-two-three-four."

Or, another standard wisecrack to runners during that unenlightened time: "Get a horse!"

"For my generation," said Centerport's Heather Williams, who won Sunday's women's 10k in 37:40, "it was, 'Run, Forrest, Run!' " -- referencing the 1994 film, "Forrest Gump."

So there still is some gap in understanding. "People definitely ask, 'Why the hell do you run? Why do that every day?' " said Huntington's 25-year-old Lindsey Block, whose second attempt at the marathon distance resulted in her 3:00:41 victory. "I don't know. It keeps me sane."

Crystal Cammarano-Perno, 30, second to Block in 3:07:29, admitted getting strange looks during training, in part because she often works out at 5 a.m. -- wearing a head lamp -- to fit around her teaching job.

A former Carey High School runner now teaching upstate, Cammarano-Perno has found that "people can be nasty," but her 2-year-old son, K.P. -- often pushed in his stroller through her daily runs -- is bound to grow up thinking distance running is a natural function.

"Oh, he knows," she said. "Mommy running."

To the shouted advice, "Get a car!" the men's half-marathon winner (1:09:24), Wantagh's 19-year-old Nick Filippazzo, sometimes bothers to answer, "I'm saving gas!" But he is convinced that "some people think running is pretty cool."

Enough, obviously, that Nassau County's roads, during this annual challenge, were filled with thousands of citizens of various ages and gaits, floating, bouncing, shuffling, trudging, slogging, sailing along.

Conversions appear to be continuing, and women's half-marathon winner, 28-year-old Jane Vongvorachoti of New Hyde Park (1:19:46), is having an impact in two countries. A dual citizen of her native United States and her parents' Thailand, where she played for eight years for the national soccer team, the Great Neck South High School grad has startled Thais when she trains on the roads there -- "A girl!" she said. "Wearing shorts!"

But, more and more, it's a runner's world. First and second in the men's 10k were Elmustafa Mchkirare, 31, of Astoria by way of Morocco (34:19) and Peter Francis, 21, of Jackson Heights and Queens College (35:54) via India.

Kat Hankinson, the 48-year-old Huntington fantasy fiction writer who won her age group (3:33:23) in her first marathon in 30 years, cited the man at her physical therapist who told her, "God invented the automobile, you know." But the days when drivers try to intimidate runners is far fewer between.

"We're ruling the world," women's marathon champ Block decided.