You've just trekked 60 miles in intermittently icy, mountainous terrain with a 40-pound pack on your back. Breathing in this thin air is as strenuous as lifting an 18-wheeler carrying a cargo of elephants. It's nightfall but there is no time to sleep and besides, treacherous creatures lurk through these woods.

Your body is so exhausted it moves on autopilot, your feet so blistered and sore they're numb. There is still another 206 miles to go on horseback, over gushing white river water and angry seas, up sheer cliff faces, across impossibly bumpy terrain on a bicycle. But this is not the self-flagellation of a Tibetan monk. This is Eco-Challenge, the three-year-old international extreme sports competition.

And although they train on the placid waters and sun-soaked, palm-lined flatlands of Key Biscayne, four South Floridians are preparing to take the challenge this August through 300 miles of the Australian outback.

The players

Tom Meier is a stockbroker with Smith Barney on Brickell Avenue. He met Luly Otero, aerobics instructor and former Merrill Lynch operations supervisor, in the gym at their Barnett Bank office building.

They were originally going to team up with Meier coworker Manny Rivera. But Rivera was injured, so they caught wind of Master Sgt. Albert Nowak, a former Army Ranger and current Florida International University (FIU) ROTC professor skilled in terrestrial navigation, as well as Capt. Blain Reeve, a U.S. Army captain.

They train each day, arriving either at the Rickenbacker Causeway at 6 a.m. for a five-and-a-half-mile run, the wall at the Eden Roc Spa for a climb, the waters off the Rickenbacker Causeway to kayak, the shores of Miami Beach to swim laps, a fitness center to take a "spin" (a rigorous stationary bicycle) class or the gym every day, sometimes twice a day, to pump iron.

One Sunday at sunrise, Team Miami Project--so named because the team is raising money for the trip and giving part to the Miami Project to Cure Paralysis--arrived on the FIU campus for a two-hour backpacking trek and orienteering class along Tamiami Trail. All this on top of the in-line skating, beach volleyball, raquetball, two-on-two basketball and other activities the team members do for fun.

"This is our full-time job," joked Meier, who somehow manages to hold down a demanding job to support his wife and three children through all of this.

For Otero, working out so frequently is nothing new. She has been a personal trainer and aerobics instructor for the past seven years, including classes at the Key Biscayner Fitness Club, as well as an extreme sportshead, skiing, bungee jumping, sky diving and backpacking whenever she gets some time off.

"I'm an adrenaline junkie, basically," she explained.

"She is. She's one of the toughest people I've met. I wish I could clone her because I need another team member," Meier said at the time of Rivera's injury.

Meier played college football and has since participated in various road races. Although you can't tell until he changes from his corporate garb to his workout clothes, he has been weight lifting close to 20 years.

"I'm just a frustrated jock," he joked.

"And he's ripped [muscular]," Otero chimed in, laughing.

Meier, who has rafted in Aspen, Col., climbed in the Grand Teton mountains and taken a 40-mile backpack trip through Yosemite National Park, started his quest to get the team together after seeing television news coverage on Eco-Challenge last year.

"I've done a lot of outdoors things that impressed me," he explained, "but they never pushed me athletically."

The opponents

Meier, Otero, Nowak and Reeve will compete against 160 other racers from around the world, some of whom are full-time athletes, Navy SEALS and those in other physically demanding professions.

Team members must remain within 100 yards of one another. They may use compasses but not electronic Global Positioning System, radio or cellular phone equipment. They must also carry safety equipment, food, sleeping gear and other necessities.

The average team sleeps two hours a night, which is the amount of sleep our four South Florida friends are shooting for. Between the physical overexertion, the harsh elements, no more food than can be carried on one's back and sleep deprivation, these competitors will likely to be maxed out, to say the least.

"You look at all the people who are in the race and they're not the most physically powerful people in the world," Meier explained, "but mentally they're the toughest people in the world. They don't break easily."

"The reason we have to push ourselves so hard is when it's day six and we're tired, our mental stamina will have to take over," he added.

This is important, since if just one member drops out of the race, the entire team is disqualified.

But, Otero added, the team expects to get touchy feely from time to time. "I think we're all going to cry at some point," she said. "There's no doubt that emotions are going to fly.

"You get four different personalities and you put them together for 10 days, there are going to be emotional outbursts."

Despite the intense competition and trying conditions, team members say they are confident they will succeed.

"One of our greatest assets is we all have the same idea of what we want to do with this race," Meier explained. "We want to go out there, compete and finish the race. We don't have individual interests in mind."

The game

The original Eco-Challenge took place in Utah in 1995 and was open to anyone willing or crazy enough to submit themselves to such physical duress.

Last year's race was held in British Columbia and boasted more than 70 teams. However, only 14 teams finished, creating a logistical nightmare for rescue crews and convincing this year's organizers to make it an invitation-only competition for experienced extreme sportsmen.

The 1996 challenge required five-member teams, but this year's asks for four-member teams and, unlike past Eco-challenges, does not provide support staff for carrying supplies and other necessities.

Teams must be comprised of either three men and one woman or three women and one man.

The South Florida team will fly to Cairnes in Queensland, Australia, on August 6, a two-day trip, then take a couple of days to overcome jetlag and begin the 10-day race on Aug. 12. Their goal is simply to finish the race.

The race includes six legs: trekking with 30- to 40-pound backpacks; canyoneering; whitewater rafting on a class IV-V river; ocean kayaking over the Great Barrier Reef; mountain biking; and horseback riding.

The team will not know which leg they will conquer or how many miles it will be until the last minute. Event organizers will sneak in additional activities, such as canoeing, to one or more of the legs. Except for Dark Zones in which certain activities, such as rafting, are forbidden at night for safety reasons, most of these activities will also be done at night.

"Part of the race also is that they don't tell you everything...A lot of that unknown is part of the mystique and the difficulty of the race," Meier said.

Along the way, team members will have to contend with big goannas, a type of dangerous lizard; pythons; poisonous snakes including the death adder that make American rattlesnake venom pale in comparison; wild pigs; crocodiles; kangaroos; leeches; 2,000 species of spiders; and stinging trees.

The trip will cost about $25,000 altogether, including $15,000 in equipment, such as smoke signals, waterproof flashlights, life jackets, climbing harnesses, head lamps and first aid kits. To cover team expenses and to give the Eco-Challenge another dimension, the South Florida team is raising money, part of which will go to the Miami Project.

Team members say they expect all these elements to come together to make the race one of those life-transforming epiphanies that churn out completely different people than the ones who came into the experience.

"The race to me almost emulates life itself," Meier explained. "There's going to be challenges along the way. There's going to be disappointments."

One of the life lessons team members say they expect to really get is that you really can't fool Mother Nature.

Otero said she is enthralled and honored "to be a part of something that is greater than life. I don't think nature is conquerable but it is...," she said, trailing off.

Meier finished for her. "...But it is something we have to work with. We have to adapt to whatever comes our way. We're not there to dominate nature. We're there to work with it."

But there is another sort of conquering that will go on, a conquering of uncharted inner territory.

"In part it's conquering some sort of inner fear," Otero said, "and it's definitely a conquering of my physical endurance, my ability to go beyond anything I thought I could ever do.

"Just being there, just being a part of it is an accomplishment on its own...," she continued, adding that after the race, Nepal will be her next challenge. "You feel like an astronaut."

Meier agreed. "It's a personal accomplishment," he said. "It's pushing myself to the limit. That's the type of person I am."