FOR AN INCREASING number of mountaineers, winning the game has become more important than how you play.

Richard Salisbury, a former computer programmer at the University of Michigan, and Elizabeth Hawley, longtime Kathmandu journalist and expedition archivist, recently published a CD-ROM called the Himalayan Database, a statistical record of all expeditions that have climbed in the Nepal Himalayas from 1904 to 2004. For the first time, we can study the act of mountaineering using science, rather than anecdotes.

From 1950 to 2004, out of the 11,734 people who went above Everest Base Camp, 2,251 made summit bids. Of these, 2,119, or 94 percent, used oxygen; 131, a mere 6 percent, did not.

What does it really mean, physiologically, to use oxygen at high altitude? "Inhaling oxygen at two to four liters per minute—a typical flow rate for climbers—reduces the height of Everest by 5,000 to 9,000 feet," explains San Diego high-altitude physiologist Dr. Brownie Schoene. In other words, climbing Everest (or K2 or any other 8,000-meter peak) with oxygen brings the peak down to around 20,000 feet at rest and 24,000 feet while climbing. That's lower than dozens of other Himalayan peaks.

"Oxygen is a performance-enhancing substance," continues Schoene. "Using oxygen in high-altitude mountaineering is like blood doping in cycling."

John Harlin III, editor of The American Alpine Journal, says using oxygen is a form of aid climbing—relying more on gear than your own ability. "The reality is, Hillary and Norgay did not make the first true ascent of Everest," he says. "In fact, it wasn't until Messner and Habeler summited Everest that the mountain was really climbed."

Today, in the 21st century, using oxygen in the mountain-climbing game is bad style, but in my opinion it is also unethical. Why? Because if you didn't carry it up (and scarcely anyone does), a Sherpa did. Unlike using porters to pack gear into a base camp, getting oxygen tanks up to a high camp is hazardous work: In the past half-century, 119 climbers have died on Everest, along with 60 porters, more than two-thirds of whom were putting in fixed lines and hauling oxygen and supplies for clients. Enlist a Sherpa to carry your oxygen and you are paying someone else to assume your risk.

In order to safely move bottled oxygen and other supplies up to high camps, Sherpas put in fixed ropes. Clients subsequently clip into these lines and march up the steps kicked in the snow by Sherpas. Wouldn't this be considered unsportsmanlike in other games? Imagine using a step ladder to dunk a basketball. More important, by relying on a fixed line, you're missing the chance to lead a pitch with ice ax and crampons, skill and resolve. You're missing out on the joy of climbing.

Fixed lines contribute to the despoliation of our mountains. They allow an excess of equipment—extra food, oxygen tanks, computers, iPods, etc.—to be carried to high camps, and much of it is never brought back down. Even the fixed lines themselves are often not removed, leaving yet more debris on the peak. Leave No Trace has been a maxim for backpackers for decades, and yet this basic principle is frequently ignored in mountaineering.

I realize that eliminating supplemental oxygen, and all it entails, from 8,000-meter peaks would have serious consequences. Because oxygen increases the margin of safety, climbing without it might increase the death rate. Everest guides often use oxygen to help them make clearheaded decisions, Sherpas use it to accompany clients, clients use it just to keep moving—so perhaps, without oxygen, Everest and K2 could no longer be commercially guided. Certainly, at least in the short term, this would financially stun the outfitters, their several dozen guides, and several hundred high-altitude Sherpas. But these outfitters guide many other peaks. All the other 8,000-meter summits—Nanga Parbat, Shishapangma, Makalu, Dhaulagiri—most of them more technically challenging than Everest, would still be there, not to mention the rest of the world's splendid mountains.