Lance Armstrong is shooting for a record seventh-straight victory in the Tour de France this July. Back home in Texas, researcher Edward Coyle, PhD, has a bird's eye view on Armstrong's stunning success.

Coyle, a kinesiology and health education professor at the University of Texas at Austin, is not just a fan. He studied Armstrong for years, starting before the cyclist's first Tour de France victory.

Coyle shares his findings in the Journal of Applied Physiology. It's an inside look at Armstrong's remarkable rise in muscular efficiency despite cancer. It's also a case study in natural talent, hard work, and perseverance.

"Clearly, this champion embodies a phenomenon of both genetic natural selection and the extreme to which the human can adapt to endurance training performed for a decade or more in a person who is truly inspired," writes Coyle.

Read WebMD's "Staging Your Personal Tour de France"

The Early Days

Coyle studied Armstrong from 1992 to 1999 -- the year of Armstrong's first Tour de France win. In 1993, the 22-year-old Armstrong had become the youngest winner of the World Championships in bicycle road racing. He had also been a competitive swimmer, runner, and triathlete in his teens, says Coyle.

Obviously, Armstrong was an elite athlete when the two first met. But no one knew what the future held.

Every year, Armstrong rode a stationary bike for Coyle's study. That bike got the workout of its life. Armstrong pedaled for 25 minutes each time at up to 90 percent of his maximal oxygen consumption, called VO2max. Meanwhile, he breathed into lab equipment that measured oxygen output and gave blood samples afterward.

Read WebMD's "Better Late Than Never for Exercise"

Putting Cancer in its Place

The yearly tests hummed along until October 1996. That's when Armstrong learned he had testicular cancer, which had spread to his lungs and brain.

Draining treatments didn't sideline him for long. "During the third and fourth month after chemotherapy, he cycled about five days per week for two to five hours per day at moderate intensity," says Coyle. Armstrong ramped up the intensity during the next two months before taking a six-week break from endurance training.

Before his next session with Coyle -- eight months after chemo -- Armstrong was cycling again for up to two hours a day, with heart rates of 120-150 beats per minute. By the time he rode for Coyle, he showed "no ill effects from his previous surgeries and chemotherapy," says Coyle.

Read WebMD's "Athletes Who Beat Cancer May Help Cancer Kids Do the Same"

Off-the-Charts Results

Over the years, Armstrong cranked up his muscular efficiency by 8 percent, says Coyle. Armstrong also became even leaner before the Tour de France, trimming his weight and body fat before the race as planned. That added up to an 18 percent rise in Armstrong's power-to-body weight ratio, says Coyle.

What's more, Armstrong's blood samples showed very low levels of lactate, a natural by-product of exercise. Armstrong's posttest lactate levels were lower than other competitive cyclists, says Coyle.

Armstrong's years of intense training may have changed his muscles' fibers, says Coyle. He didn't take any muscle samples from Armstrong to check that.

This year's Tour de France runs from July 2-24. It covers more than 2,200 miles in 21 stages and finishes in Paris.

By Miranda Hitti, reviewed by Michael W. Smith, MD

SOURCES: Coyle, E. Journal of Applied Physiology, June 2005; vol 98: pp 2191-2196. News release, American Physiological Society. Tour de France 2005.