One week after 400 mountain bikers lined up here to "race across the sky" on 100 miles of trails, almost 400 more athletes are back to try to accomplish a similar task with one major difference: running shoes don't coast.

It's also safe to say the Leadville Trail 100 Running Race course records will hold up better on Saturday than the mountain bike records did last weekend.

The 2nd Annual Leadville Trail 100 Mountain Bike event saw Russell Worley of San Diego, California topple John Stamstad's 1994 winning time by more than 30 minutes, while Laurie Brandt of Louisville, Colorado dropped under the nine-hour mark to surpass her own record.

There is little chance that anyone will come in under the men's and women's running records set last year by first-place finishers Juan Herrera and Ann Trason.

Both Trason and Herrera (a member of Mexico's Tarahumara tribe) will bypass this year's event, which means they'll miss the trek over and back across Hope Pass (at 13,000 feet), the mid-point of the 13th annual epic endurance race.

After all, their strong performances last year means they've left little to prove this year.

Herrera turned in a time of 17 hours, 30 minutes and 42 seconds to break Jim O'Brien's course record set in 1990 by 35 minutes. And Trason decimated her own record, also set in 1990, by two hours and 32 minutes with a time of 18:06:24.

"They didn't enter, and we filled up about two weeks after we sent out registration forms in January," said race director Merilee O'Neal.

Reportedly, Trason is concentrating her efforts on competition with the United States 100K International Team.

Herrera and his fellow Tarahumara, who eschewed Nikes for running shoes fashioned from old tires at the Leadville town dump last year, were last seen at the Western States 100 in June.

No doubt, Trason and the enigmatic Tarahumara, hailing from the Sierra Madre's Copper Canyon in Chihuahua, Mexico, will be missed when the entrants take off at 4 a.m. Saturday. But records and competition are only half of the Leadville 100's magical attraction.

The other half has to do with everyday people, training all year round so that they can come to Leadville and achieve a goal. For most it is simply to reach the finish line before the 30-hour cutoff. Traditionally, only half of the field makes it, so that arriving back in Leadville often means the most to those in the back of the pack.

"I think this race and maybe others like it have been instrumental in pushing our ideas of what limits are," said O'Neal. "Finishing this race actually changes people's lives... the way they look at their lives when they're successful here. It opens up your whole life to new possibilities."

Gant Enderle is a reporter with the Vail Daily News in Colorado