Searchers on Saturday found the body of renowned long-distance runner Micah True, who vanished four days earlier after heading out from a lodge for a morning run in the rugged wilderness near New Mexico's Gila National Forest.

The body was discovered in a remote area of the Gila Wilderness, state police spokesman Lt. Robert McDonald said.

The cause of death was still unknown, but there were no signs of trauma, incident commander Tom Bemis said.

"It's too early to say, there was nothing obvious," he told the Boulder Daily Camera.

The 58-year-old True, whose extreme-distance running prowess is detailed in the book "Born to Run," set out on what -- for him -- would have been a routine 12-mile run Tuesday from The Wilderness Lodge and Hot Springs, where he was staying. He left his dog at the lodge and never returned. A search began the next day after.

Lodge co-owner Dean Bruemmer, who helped with the search Saturday, said he last saw his friend at breakfast. He said True gave no indication of a specific route, which made the search more difficult.

"There are a lot of trailheads up the road," said Bruemmer, whose lodge is about four miles from the Gila Cliff Dwellings National Monument.

Though daytime temperatures in southwest New Mexico have been mild of late, temperatures have dipped into the mid-20s on recent nights. True left for his run wearing only shorts and a T-shirt and carrying a water bottle.

Fourteen search teams that were scouring the area Friday were supplemented with additional volunteer teams from across the state Saturday morning, McDonald said. Teams were hiking and on horseback and ATVs. They also used dogs and employed a helicopter and plane in the search.

True, who had been friends with Bruemmer and his wife, Jane, for 10 years, would often visit their lodge while traveling between Mexico and his Boulder, Colo., home. As a result, Bruemmer said, True certainly knew the trail system well -- which made his disappearance all the more mystifying to everyone.

Michael Sandrock, a columnist who writes about running for The Daily Camera newspaper in Boulder, knew True for at least 20 years and had run with him. He called True a pioneer of the sport of ultrarunning, which involves running extreme distances, often on grueling terrain and many miles longer than a traditional 26-mile marathon.

True, he said, had a rebellious spirit but never sought to draw attention to himself even as he became legendary for his talents, which included "just going up and running for hours and hours at a time."

"He's just authentic and genuine. ... Micah is a guy who follows his bliss," Sandrock said.

True was the race director of The Copper Canyon Ultra Marathon, a 50-plus mile extreme race that took place in Urique, Mexico, on March 4.

He was featured in articles in running magazines and was a central character -- known by his nickname, "Caballo Blanco" -- in Christopher McDougall's nonfiction best-seller "Born to Run."

"He's such an integral part of the fabric of the ultra community," Sandrock said. "He's one of the stars .... the Caballo Blanco, he's a legend."