MURRAY — With the firm, slow steps that he used to climb the world's tallest mountain in record time, Lhapka Gelu Sherpa trudged on a treadmill at The Orthopedic Specialty Hospital.

The medical testing at TOSH on Tuesday was part of a study that medical researchers are hoping will help them better understand the unique athleticism that allowed Lhapka to climb Mount Everest in just under 11 hours.

Also participating in the testing was Apa Sherpa, who has reached Everest's summit a record 16 times. The two will also be tested when they return to Nepal this spring to lead an all-Sherpa team to the 29,035-foot summit.

"These are top athletes, what they do is kind of unique," said Dr. Max Testa, a sports medicine physician. "They don't really train like modern athletes."

However, the Sherpas live their lives at high altitude and walk everywhere, he said, adding, "They walk three hours to get to the grocery store."

The "Super Sherpas" expedition isn't only for medical research. It will be the subject of a documentary and book to raise awareness of the Sherpa people. At least 25 percent of the proceeds will go to Nepali schools, hospitals and other deserving entities.

Through the medical research, doctors are hoping to discover how the world's fittest high-altitude climbers operate.

"We measure them the same way as athletes in traditional sports," Testa said. "Once we create a function of the sport ... we can design a training program to climb Everest." Such a program would help not only average people who want to climb mountains, but could help the Sherpas themselves train more effectively, he said.

Testa said while there has been research on the Sherpas' ability to live at high altitude, Sherpas have not been studied before as athletes. Also, the two Sherpas have been living in Utah since late last year. Most testing of Sherpas has been at high altitude in Nepal.

The research was designed to closely mimic the athletes' condition as they climb. They were fed a breakfast nutritionally similar to what they'll eat on Everest.

And as the two walked on the treadmill at various inclines, they each wore a pack weighing 55 pounds.

However, as the researchers discovered during a trial run to acclimate the Sherpas to the treadmill, neither had used one before. The treadmill's steepest angle isn't as steep as some slopes the Sherpas will climb on Everest, Apa said. And at first, the treadmill was set too fast for the slow pace of high-altitude climbing.

After he got used to the treadmill, Apa described it as "good practice."

As they walked on the treadmill the Sherpas wore wore heart monitors and breathed into a device that measures functions such as how much oxygen the body is using, how the body is using fuels such as fats and carbohydrates, and breaths per minute.