As someone who lives just a few hundred paces from the Boston Marathon course, I've cheered my share of athletes. This year, it was Masazumi Soejima at the head of the pack, propelling his wheelchair across a rainy 26 miles in 1 hour, 29 minutes and 16 seconds. It took Robert Cheruiyot an extra 44 minutes and 57 seconds to come in first on foot.

I take nothing away from the athleticism and grit of Soejima. But it goes without saying that he didn't "beat" Cheruiyot. Those who compete on foot and those who compete with wheels are categorically different. And succeed in different categories.

I make this point because of the controversy surrounding a 20-year-old South African named Oscar Pistorius. This racing phenom recently won the 100- and 200-meter races in an international competition for disabled athletes. He won on a pair of J-shaped carbon fiber blades known as Cheetahs.

Pistorius calls himself "the fastest man on no legs." He was born with defects in his feet, and his lower legs were amputated when he was 11 months old.

Nevertheless, he says, "I don't see myself as disabled."

He wants to be allowed to race for the Olympic gold on his own two Cheetahs.

This is one of those stories tailor-made for the Olympic coverage: A great athlete overcomes enormous adversity to pursue his dream! But it's also one of the other stories now stalking sports: Exactly what kind of technology, training or performance enhancements should we applaud? And what kind should we reject?

This conversation seems to be as common as box scores and doping scandals. On the baseball field, Barry Bonds is creeping up on Hank Aaron's home run record. But there is no joy in Mudville. Bonds' achievement is tainted by the belief that he used steroids to beef up his body and his record.

In cycling, where doping is the bane of the Tour de France, Floyd Landis' inspiring win turned sour with lab reports of testosterone shots. He is still fighting for his crown and his reputation.

Those who oppose Pistorius compare his Cheetahs to "techno-doping." But it is also true that technology has been used to enhance performance since the first runner put on a shoe and this duffer put Big Bertha in her golf bag.

Training has reached a level of technical sophistication unheard of when Roger Bannister broke the four-minute mile. Athletes train in wind tunnels and travel to high altitudes. But the use of altitude tents to simulate that "high" has been decried as violating the "spirit of the sport."

And what are we to make of Lasik surgery that gave the near-sighted Tiger Woods his 20/15 vision and four straight championships right afterward? Is better-than-perfect vision a kind of enhancement like doping or a correction like contact lenses?

Some years ago, I questioned a beauty pageant in which the contestants had been surgically altered and implanted. They didn't owe their beauty to their maker but, rather, to their remaker.

Similar questions about the remanufacture of athletes, says ethicist Tom Murray, "force us to ask what is the point of sport. Whatever we think is meaningful and beautiful about sports has to do with the ways we admire natural talents and hard work and dedication."

But there are other things we don't admire. "I can climb the mountains of the Tour de France faster than all the other competitors," quips Murray. "All I need is a motor."

Today, we replace hips and knees with titanium. We replace thyroids with pills. NBC is remaking the "Bionic Woman" series for a new run, and ethicists are debating the possibility of real bionic athletes.

Michael Sandel, author of "The Case Against Perfection," warns that "part of what we admire about great athletes is that we are able to see ourselves in their human achievements." Who would applaud the bionic Olympiad?

As for Pistorius and prostheses? So far, the International Association of Athletics Federations has prohibited him from the Olympics. The final decision won't come till August.

But what makes his challenge so compelling is not just his extraordinary courage and talent. His prostheses both enable a disabled man and offer an athlete high-tech equipment. They land somewhere between a sophisticated running shoe and a motor.

I don't think that Cheetahs are cheating. And I am uncomfortable with the talk of cyborgs and transhumans that surrounds this case. These stories will get harder, not easier, over the next years.

But as a fan of Masazumi Soejima, I don't think that racing on a separate track is an insult. It's still the right place for the "fastest man on no legs."

Ellen Goodman is a columnist for The Boston Globe. Reach her at ellengoodman@globe.com.