Published in The New York Times Magazine
January 18, 2004

On a brisk day last month, I was led through a warren of red brick buildings on the campus of the University of Pennsylvania in West Philadelphia and then up to a fifth-floor molecular physiology laboratory. I had come to visit some mice -- and to get a peek at the future of sport.

I had heard about these mice, heard them called "mighty mice," but I was still shocked at the sight of them. There they were in several small cages, grouped with normal mice, all of them nibbling on mouse chow pellets. The mighty mice looked like a different animal. They were built like cattle, with thick necks and big haunches. They belonged in some kind of mouse rodeo.

The Penn researchers have used gene therapy on these mice to produce increased levels of IGF-1, or insulinlike growth factor-1, a protein that promotes muscle growth and repair. They have done this with mice before birth and with mice at four weeks of age. A result has been a sort of rodent fountain of youth. The mice show greater than normal muscle size and strength and do not lose it as they age. Rats altered in the same fashion and then put into physical training -- they climb little ladders with weights strapped to their backs -- have experienced a 35 percent strength gain in the targeted muscles and have not lost any of it "detraining," as a human being will when he quits going to the gym.

To the scientists, H. Lee Sweeney, chairman of Penn's department of physiology, and Elisabeth Barton, an assistant professor, the bizarre musculature of their lab specimens is exciting. This research could eventually be of immense benefit to the elderly and those with various "muscle wasting" diseases.

"Our impetus, going back to 1988, was to develop a therapy to stop people from getting weak when they get old," Sweeney, 50, explained. "They fall and injure themselves. We wanted to do something about that."

Barton, 39, has the broad shoulders and athletic build of the competitve cyclist and triathlete she once was. "You see children with muscular dystrophy, and their parents are just so broken up because it's so sad," she said. "You see grandparents who can't get out of bed. These are the people this is for."

But the Penn team has become acutely aware of a population impatient to see its research put into practice -- the already strong, seeking to get stronger still. Sweeney gets their e-mail messages. One came from a high-school football coach in western Pennsylvania not long after Sweeney first presented his findings at a meeting of the American Society for Cell Biology. "This coach wanted me to treat his whole team," he said. "I told him it was not available for humans, and it may not be safe, and if I helped him we would all go to jail. I can only assume he didn't understand how investigational this is. Or maybe he wasn't winning, and his job was on the line."

Other calls and e-mail messages have come from weight lifters and bodybuilders. This kind of thing happens often after researchers publish in even the most arcane medical and scientific journals. A whole subculture of athletes and the coaches and chemists who are in the business of improving their performances is eager for the latest medical advances.

Sweeney knows that what he is doing works. The remaining question, the one that will require years of further research to answer, is how safe his methods are. But many athletes don't care about that. They want an edge now. They want money and acclaim. They want a payoff for their years of sweat and sacrifice, at whatever the cost.

"This was serious science, not sports science," Dr. Gary Wadler, a United States representative to the World Anti-Doping Agency, said when I spoke to him about the Penn experiments. "As soon as it gets into any legitimate publication, bango, these people get ahold of it and want to know how they can abuse it."

Sweeney's research will probably be appropriated before it is ever put to its intended medical purpose. Someone will use it to build a better sprinter or shot-putter.

There is a murky, "Casablanca"-like quality to sport at the moment. We are in a time of flux. No one is entirely clean. No one is entirely dirty. The rules are ambiguous. Everyone, and everything, is a little suspect.

Months before the great slugger Barry Bonds was summoned before a grand jury in December to answer questions about his association with the Bay Area Laboratory Co-Operative, known as Balco, which has been at the center of a spreading drug scandal after the discovery of a new "designer steroid," tetrahydrogestrinone (THG), a veteran American sprinter named Kelli White ran the track meet of her dreams at the World Championships in Paris. She captured the gold medal in the 100-meter and 200-meter races, the first American woman ever to win those sprints in tandem at an outdoor world championship. In both events, the 5-foot-4, 135-pound White, a tightly coiled ball of power and speed, exploded to career-best times.

On a celebratory shopping trip on the Champs-Elysees, White, 26, glimpsed her name in a newspaper headline and asked a Parisian to translate. She learned that she had flunked a postrace drug test and that her medals and $120,000 in prize money were in jeopardy. Later, she acknowledged that she had taken the stimulant modafinil, claiming that she needed it to treat narcolepsy but had failed to list it on a disclosure form. What she added after that was revealing, perhaps more so than she intended. "After a competition," she told reporters in Europe, "it's kind of hard to remember everything that you take during the day."

The THG scandal and the attention focused on Balco, which has advised dozens of top athletes (including Kelli White) on the use of dietary supplements, has opened the curtain on a seamy side of sport and on the fascinating cat-and-mouse game played between rogue chemists and the laboratory sleuths who try to police them.

But White's statement exposed another, deeper truth: elite athletes in many different sports routinely consume cocktails of vitamins, extracts and supplements, dozens of pills a day -- the only people who routinely ingest more pills are AIDS patients -- in the hope that their mixes of accepted drugs will replicate the effects of the banned substances taken by the cheaters. The cheaters and the noncheaters alike are science projects. They are the sum total of their innate athletic abilities and their dedication -- and all the compounds and powders they ingest and inject.

A narrow tunnel leads to success at the very top levels of sport. This is especially so in Olympic nonteam events. An athlete who has devoted his life to sprinting, for example, must qualify for one of a handful of slots on his Olympic team. And to become widely known and make real money, he probably has to win one of the gold medals that is available every four years.

The temptation to cheat is human. In the realm of elite international sport, it can be irresistible.

After Kelli White failed her drug test, the United States Olympic Committee revealed that five other American athletes in track and field had tested positive this summer for modafinil. Did they all suffer from narcolepsy? That would be hard to believe. More likely, word of modafinil and its supposed performance-enhancing qualities (perhaps along with the erroneous information that it was not detectable) went out on the circuit. It became the substance du jour.

For athletes, performance-enhancing drugs and techniques raise issues of health, fair play and, in some cases, legality. For sports audiences, the fans, the issues are largely philosophical and aesthetic.

On the most basic level, what are we watching, and why? If we equate achievement with determination and character, and that, after all, has always been part of our attachment to sport -- to celebrate the physical expression of the human spirit -- how do we recalibrate our thinking about sport when laboratories are partners in athletic success?

Major League Baseball, which came late to drug testing and then instituted a lenient program, seems to have decided that the power generated by bulked-up players is good for the game in the entertainment marketplace. The record-breaking sluggers Mark McGwire and Sammy Sosa have been virtual folk heroes and huge draws at the gate. Their runs at the record books became the dominant narratives of individual seasons. (Barry Bonds has been less popular only because of a sour public persona.) But the sport is much changed. Muscle Baseball is the near opposite of what I and many other fans over 30 were raised on, a game that involved strategy, bunting, stolen bases, the hit-and-run play -- what is called Little Ball.

Professional basketball is not generally suspected of being drenched in steroids and other performance enhancers. But anyone who has seen even a few minutes of old games on the ESPN Classic network from, say, 20 years ago, is immediately struck by the evolution of players' physiques. Regardless of how it happened, today's N.B.A. players are heavier and markedly more muscled, and the game is tailored to their strengths. It is played according to a steroid aesthetic. What was once a sport of grace and geometry -- athletes moving to open spaces on the floor, thinking in terms of passing angles -- is now one primarily of power and aggression: players gravitate to the same space and try to go over or through one another.

But it is sports that have fixed standards and cherished records that present fans with the greatest conundrum. If what's exciting is to see someone pole vault to a new, unimaginable height -- or become the "world's fastest human" or the first big-leaguer since Ted Williams to hit .400 -- how do we respond when our historical frame of reference is knocked askew by the suspicion, or known fact, that an athlete is powered by a banned substance?

In elite sport, the associations of competitors who have never been sanctioned for drug use or known to fail a drug test can still raise questions. Marion Jones, the breathtaking sprinter and featured American performer of the 2000 Sydney Olympics, was married to the shot-putter C.J. Hunter -- who was banned from those games after testing positive for the steroid nandralone. Jones later divorced Hunter, but then trained (briefly) with Charlie Francis, the disgraced ex-coach of Ben Johnson, the disgraced Canadian sprinter who was stripped of an Olympic gold medal. Carl Lewis, the greatest U.S. Olympian in history and a longtime crusader against performance-enhancing drugs -- it was Lewis who was outsprinted by the steroid-fueled Ben Johnson at the 1988 Games in Seoul -- has been accused of flunking a drug test of his own before the 1988 U.S. Olympic Trials. Lance Armstrong, brave cancer survivor, fierce and inspiring competitor, has kept up a long association with an Italian doctor in the thick of a sprawling drug scandal in Europe, although Armstrong himself has never come up positive on a drug test.

Even the substances themselves are murky. Because the $18-billion-a-year dietary-supplement industry is (at best) loosely regulated, some of the potions in the vitamin store at your local mall could well be tainted by steroids or growth hormones. The Food and Drug Administration just got around to banning the sale of ephedra last month, long after the herbal stimulant was blamed for numerous serious health problems, along with the sudden death last year of Steve Bechler, a Baltimore Orioles pitcher.

The whole situation cries out for a dose of clarity, but the closer you look, the fuzzier the picture. Start with the line between what's legal and illegal when it comes to enhancing performance. The line, already blurry, is likely over time to disappear entirely.

I visited a U.S. swimmer last September as technicians sealed up his bedroom, after which they installed equipment that reduced the amount of oxygen in his room and turned it into a high-altitude chamber. This is a common and legal training method that Ed Moses, America's best male breaststroker, said he hoped would increase his count of oxygen-carrying red blood cells. A whole team of long-distance runners sponsored by Nike lives in a much more elaborate simulated high-altitude dwelling in Portland, Ore. The desired effect of the so-called "live high, train low" method -- sleep at altitude, train at sea level -- is the same as you would get from taking erythropoietin, or EPO, which increases red-blood-cell production and is banned in sports.

Two other U.S. swimmers, in the lead-up to the Olympic Games in Sydney, were on a regimen of 25 pills a day, including minerals, proteins, amino acids and the nutritional supplement creatine, an effective but not necessarily safe builder of muscle mass. Much of the mix may well have been useless, but athletes tend to take what's put in front of them for fear of passing up the one magic pill.

"I like to think we're on the cutting edge of what can be done nutritionally and with supplements," the swimmers' coach, Richard Quick, said then as his athletes prepared for the 2000 games. "If you work hard consistently, with a high level of commitment, you can do steroidlike performances." One of his swimmers, Dara Torres, who increased her bench press from 105 pounds to 205 pounds and swam career-best times at the age of 33, said at the time that her goal was to "keep up with the people who are cheating without cheating."

And who are the cheaters? Everyone else. One primary motivation to cheat is the conviction that everyone else is cheating.

To draw the often arbitrary lines between performance enhancing and performance neutral, between health endangering and dicey but take it at your own risk -- to ensure that sport remains "pure" -- a vast worldwide bureaucracy has been enlisted.

At the lowest level are those who knock on the doors of athletes in their homes and apartments in the United States and Europe and in the mountain villages of Kenya and at the training sites in China and demand "out of competition" urine samples. Higher up on the pyramid are the laboratories around the world chosen to scan the urine (and blood) of elite athletes for the molecular signatures of any of hundreds of banned substances. At the top of the drug-fighting pyramid are the titans of international sport -- the same people who cannot see to it that a figure skating competition is fairly judged.

The titans created the World Anti-Doping Agency, which works with governments and designated national organizations, including the United States Anti-Doping Agency. In combination with the urine-sample collectors, the various couriers in the chain of custody and the laboratories, W.A.D.A. is charged with making sure that the world's premier athletes are clean -- and additionally that they have not concealed drug use through the use of various "masking agents." (The latest U.S.A.D.A. list specifically prohibits the following brand names: Defend, Test Free, Test Clean, UrinAid and Jamaica Me Clean.)

It is all an immensely complicated endeavor, one that requires W.A.D.A. to keep up with the onrushing science, to disseminate information to thousands of athletes, to navigate in different legal systems so that accused competitors get due process and, lastly, to manage the worldwide trafficking of urine samples. And it is all, in the end, quite possibly pointless.

Despite the hundreds of people and tens of millions of dollars devoted to the effort, international and national sports organizations may just lack the will to catch and sanction cheaters. The United States, specifically, has been singled out as negligent in its oversight. "The real issue is that USA Track and Field has become a complete and utter scofflaw," the W.A.D.A. president, Richard Pound, a Canadian, told me. "They have gone to extraordinary lengths to hide identities and data and to exonerate athletes who have tested positive."

Can you really have a serious antidoping effort without the full cooperation of the world's most powerful nation -- and most powerful sports nation? It's hard to see how.

The tougher question is whether it will be scientifically possible to stay ahead of the cheaters. The rogue scientists and coach-gurus have been winning for years, and they have ever more tools available to them. THG, which set off the Balco inquiry, is only a slightly more clever version of an old thing: an anabolic steroid -- the kind of blunt builder of muscle mass and strength prevalent in sports since the 1950's. But its discovery required an insider tip, and THG is child's play compared with what's coming in the near future (if, in fact, it is not here already): genetic manipulation in order to improve athletic performance.

Ultimately, the debate over athletic doping extends beyond sport. "The current doping agony," says John Hoberman, a University of Texas at Austin professor who has written extensively on performance drugs, "is a kind of very confused referendum on the future of human enhancement."

Pete Rose was the prototypical "self-made" athlete, which is code for a sort of seeming nonathlete who makes the most of his meager abilities. But fans overlooked important genetic traits that made him baseball's all-time hits leader -- chiefly, uncommon durability that allowed him to play 24 seasons virtually injury free. And what did Rose do to attain that? Nothing, really. As the son of a semipro athlete who played sandlot baseball and football into his early 40's, he came by that blocky, unbreakable body by way of genetic inheritance. In the off-season, Rose maintained himself by playing casual basketball a couple of times a week and eating greasy food and heaping bowls of potato chips.

When it comes to elite sport, there is no such thing as self-made. No amount of dedication can turn someone of average ability into a world-class sprinter, an N.B.A. player or a champion marathoner. You can't be an Olympic pistol shooter without some innate steadiness of hand or a Tour de France cyclist without a far-above-average efficiency at moving oxygen to muscles. Even a humdrum, physically unimpressive player on a major-league baseball team has something -- usually extraordinary hand-eye coordination -- that is not apparent to those who regard athletic gifts only in terms of great size, speed, endurance or power.

The former Olympic track coach Brooks Johnson once told me that sport at its highest level should be viewed as a competition waged among "genetic freaks." He mentioned Carl Lewis and Michael Jordan. But anyone who reaches the top echelon of Olympic competition or draws a paycheck for playing sports professionally should be considered in the same category. You cannot will yourself into an elite athlete, or get there through punishing workouts, without starting out way ahead of the rest of the human race.

You may, through pure dedication, be able to jump one level -- from a middle-of-the-pack Olympic sprinter to the final heat, from a marginal N.F.L. prospect to a midround draft pick. Chemical enhancement can produce more significant improvements, but the principle is the same. You've got to start out as a member of the athletic elite.

At the 1996 Summer Olympics in Atlanta, a middling Irish swimmer named Michelle Smith de Bruin raised suspicions when she won three gold medals. She later flunked drug tests. But before the presumed cheating, she was already a competitor on the international swim scene, not a lap swimmer at the Dublin Y.

The use and abuse of performance-enhancing drugs in elite sport, or doping, as it has been called since around 1900, is a mutant form of an exclusive competition. It is an effort by individuals who are already part of a thin slice of humanity -- the genetic freaks -- to gain an edge against one another, to exceed their physiological limits in a way that they could not through pure training. (The word itself is believed to derive from the Dutch word dop, an alcoholic beverage consumed by Zulu warriors before battle.)

While systematic doping -- with the collaboration of chemists, doctors, coaches and trainers -- is a modern phenomenon, scientific interest in athletes is not new. The medical establishment once viewed athletes with curiosity and occasionally with alarm. The act of training and pushing yourself to physical limits was considered dangerous or even a form of sickness. Sports science was observational, an opportunity to study the body in motion by looking at individuals at the extremes of human capacity.

The British physiologist A.V. Hill, a Nobel laureate in 1922, went to Cornell to study sprinters because, as he wrote, "matters of very great scientific interest can be found in the performances of that extraordinary machine, the human athlete." John Hoberman, the historian of sports doping, has written that scientists and doctors viewed the high-performance athlete as "a wonder of nature -- a marvelous phenomenon that did not require improvement."

Certainly, athletes have long sought their own chemical and nutritional means to enhance performance. The ancient Greeks ran and wrestled in the nude because nothing, not even fabric, was supposed to interfere with the purity of sport, yet they ate mushrooms, sesame seeds, dried figs and herbs that were believed to give a precompetition energy boost. Marathoners and cyclists as recently as a century ago competed under the influence of strychnine, which is both a stimulant and a poison. Cyclists also used caffeine, cocaine, alcohol and even heroin.

What changed everything -- what transformed performance-enhancing efforts from the realm of superstition into a true science -- was the isolation of the male hormone testosterone in 1935. That led to the development by the late 30's of synthesized testosterone variants, or anabolic steroids. The difference between steroids and all previous performance enhancers was that steroids demonstrably worked -- and they worked really well.

Nearly every drug used by athletes to boost performance started out as a therapeutic miracle.

Steroids are still prescribed for men with serious testosterone deficiencies. AIDS patients and others with muscle-wasting conditions are dosed with steroids.

Until the mid-80's, people suffering from severe anemia, as a result of chronic renal failure or other causes, had to undergo frequent blood transfusions. The development of recombinant human erythropoietin was a godsend. Instead of transfusions, anemics could get injections to boost their red-blood-cell count.

But what would the effect of EPO be on a person with a normal or better than normal red blood count? What could it do for an already genetically gifted, highly trained endurance athlete? Just what you would expect: make a superendurance athlete.

EPO swept the professional cycling circuit in Europe like a plague, nearly wrecking the sport. There were police raids, huge stockpiles of EPO confiscated from cyclists' hotel rooms, arrests, trials, wholesale suspensions of competitors. "Each racer had his little suitcase with dopes and syringes," a former doctor for European professional cycling teams told a British newspaper. "They did their own injections."

EPO migrated to other endurance sports, including cross-country skiing, marathoning and orienteering. Inevitably, it showed its fatal flip side.

"In simplest terms, EPO turns on the bone marrow to make more red blood cells," says Gary Wadler, the American delegate to W.A.D.A. "But there's a very delicate balance. You can have too much EPO. The body is a finely tuned instrument. It has feedback mechanisms to keep it in balance. What these athletes are often trying to do is get around the feedback, to trick their own bodies."

Between 1989 and 1992, seven Swedish competitors in orienteering -- a mix of running and hiking that is sometimes called "cross country with brains" -- died, apparently from heart attacks. Nearly all were in their 20's. As many as 18 Dutch and Belgian cyclists died under similarly mysterious circumstances between 1987 and 1990.

"At first they said it was some kind of virus, a respiratory virus," Wadler says. "But what kind of virus only knocks off the most fit individuals in their country? The autopsies were private. All the deaths were not definitively linked. But it was EPO. That was obvious to a lot of people."

For weight lifters and competitors in the "throwing" sports of shot-put, javelin, discus and hammer, the performance enhancer of choice has long been steroids. Anabolic steroids (anabolic means tissue building) increase muscle mass and enhance the explosiveness needed for a wide range of other athletic endeavors: sprinting, jumping, swimming, serving a tennis ball, swinging a baseball bat, delivering a hit on the football field. They afford an additional benefit in a violent sport like football because one of their side effects is aggressiveness or, in extreme cases, so-called roid rage.

Their use is starkly high risk, high reward. Other side effects include liver tumors, impotence, breast enlargement and shrunken testicles in men and male sexual characteristics in women. (Some of the side effects for women include enlargement of the clitoris, deepening of the voice, facial hair and male-pattern baldness.)

If you want a peek at the future of performance-enhanced sport -- at what drug-laced athletes can accomplish -- look back to the mid-80's, the apex of East Germany's shameful and ruthlessly effective doping program. The East Germans were not the only practitioners of extreme pharmacological sport, only the most flagrant and well organized. (East Germany is the only nation known to have systematically doped athletes, often minors, without their knowledge.)

"Things really got out of hand in the 1970's, 80's and 90's," Richard Pound of the W.A.D.A. says. Even as the science of detection improved, the International Olympic Committee and other global sports bodies were constrained, he says, by a "hesitancy to offend" either side while the world was still divided between East and West. "We looked away, and it snowballed."

Steroid usage works particularly well for women athletes, because they naturally make only a fraction of the testosterone that men produce. John Hoberman says: "In the 80's, what we saw was this new breed of monster athletes, particularly on the female side."

Certain records from this heyday of unpoliced steroid abuse -- particularly in sports in which raw strength is a primary requirement -- suggest that performances were achieved then that are unlikely to be matched by a clean competitor. The top 14 men's hammer throws in history occurred between 1984 and 1988. In the women's shot-put, you must go all the way down to the 35th farthest throw in history to find one that occurred after 1988.

Until last April, the top 10 men's shot-put throws in history occurred between 1975 and 1990. Then, at a competition in Kansas, the American shot-putter Kevin Toth finally broke into that elite group. His distance, 22.67 meters, was the farthest that anyone had put the shot in 13 years. Six months later, Toth's name was among the first to surface in the Balco scandal. Published reports said he had tested positive for THG, the new designer steroid.

In women's sprinting in the 80's, the star -- and still the world-record holder in the 100- and 200-meter dashes -- was Florence Griffith Joyner, FloJo. Americans loved her style, her body-hugging track suits, her long and fabulously decorated nails, her ebullience. Elsewhere in the world, and even in the United States among those with a knowledge of track and field, FloJo's exploits were viewed with more skepticism.

After Joyner died in 1998, at 38 (the cause was related to a seizure), a strange hybrid of a column appeared in the New York Times sports section. Written by Pat Connolly, who had coached Evelyn Ashford, the woman whose 100-meter record Joyner smashed, it was partly a tribute and partly a posthumous indictment. "Then, almost overnight, Florence's face changed -- hardened along with her muscles that now bulged as if she had been born with a barbell in her crib," Connolly wrote. "It was difficult not to wonder if she had found herself an East German coach and was taking some kind of performance-enhancing drugs."

FloJo had been a very good, but never a champion, world-class sprinter. Her 1988 performance in Seoul was -- in the damning parlance of international sport -- anomalous.

We don't normally think of baseball in the context of hammer throwing, shot-putting or women's sprinting. But in terms of anomalous performance, baseball is East Germany in the 1980's: a frontier.

Just as in the steroid-drenched days of Olympic sport, a deep suspicion has attached itself to some of the latest records in baseball. This accompanies the grotesqueness of the appearance of some of the players. Curt Schilling, the All-Star pitcher, memorably told Sports Illustrated in 2002, "Guys out there look like Mr. Potato Head, with a head and arms and six or seven body parts that just don't look right."

I'm not sure whom, exactly, Schilling had in mind, but for me, his comment recalls a particular photograph taken in the 2002 season. The subjects are the home-run kings Barry Bonds and Sammy Sosa, sitting together, both of them with thick necks and bloated-looking faces. They look, well, freakish -- as well as starkly different from their appearance as young players. Bonds entered baseball lean and wiry strong, much like his late father, the All-Star outfielder Bobby Bonds. Sosa, early in his career, was not particularly big and showed little power at the plate.

The question of how many home runs it is possible to hit in one season is more open-ended than, say, the fastest possible time a person can achieve in the 100-meter dash. Factors like the size of the ballpark, liveliness of the ball and skill of opposing pitchers affect the outcome. Nevertheless, a century's worth of experience amounted to a pretty persuasive case that around 60 home runs, for whatever combination of reasons, was about the limit.

In 1927, Babe Ruth slugged 60, which remained the record until 1961, when Roger Maris (in a slightly longer season) hit 61. But in 1998 Mark McGwire of the St. Louis Cardinals obliterated Maris's record by hitting 70 home runs.

Late in that season, a reporter snooping around McGwire's locker spotted a bottle of androstenedione, or andro, a substance usually described as a steroid "precursor" that provides a steroidlike effect (and that is still unregulated in the major leagues). McGwire was forced to acknowledge that his strength was neither entirely "God given" nor acquired solely in the weight room. But at least McGwire entered baseball already big and as a prodigious home-run hitter; he hit 49 in his first big-league season, a record for rookies. Contrast that with the career arcs of Bonds and Sosa, which are unlike any in the game's long history.

Bonds had never hit more than 46 home runs until the 2000 season, and in most years his total was in the 30's. But at age 35, when players normally are on the downside of their production, he hit 49 home runs. The following season he turned into superman, breaking McGwire's record by hitting 73.

Bonds's totals in the next two seasons, 46 and 45, were artificially low because pitchers walked him a staggering 346 times. His new capabilities had thrown the balance between pitcher and hitter completely out of whack: the new Barry Bonds was too good for the game. He needed a league all his own.

Sosa's progression was even more unusual. In his first eight major-league seasons he averaged 22 home runs, although his totals did steadily increase and he hit 40 in 1996, then a career high. He was selected an All-Star exactly once. Unlike Bonds, he was not considered among baseball's elite players.

Then in 1998, McGwire's record-breaking year, Sammy Sosa hit 66 home runs -- 6 more than the great Babe Ruth had hit in his best season. Sosa wasn't done. The following year he hit 63, followed by seasons of 50, 64 and 49 -- the best five-year total in baseball history.

That there is rampant steroid use in baseball, at all levels, is undeniable. Ken Caminiti, the 1996 National League M.V.P., admitted his own use in a Sports Illustrated article in 2002 and estimated that at least half the players in the big leagues built strength with steroids. The former slugger Jose Canseco has acknowledged steroid use. In a 2002 USA Today survey of 556 big-league players, 44 percent said they felt pressure to take steroids.

Last year, The Washington Post published a sad series of stories revealing that teenage prospects in the baseball-rich Dominican Republic, the source of nearly one-fourth of all players signed to U.S. pro contracts, are taking veterinary steroids to try to get strong enough to attract the interest of scouts.

Whether Sosa and Bonds have built home-run power chemically cannot be known definitively. Nobody has presented evidence that they have, and both vehemently deny it. Sosa's name has not surfaced in the Balco case, and he has not testified before the grand jury.

Bonds did testify in December. The home of his personal trainer and boyhood friend, Greg Anderson, has been searched by federal agents. Bonds has acknowledged patronizing Balco, which under Victor Conte, its founder, has specialized in testing athletes' blood to determine the levels of elements like copper, chromium and magnesium and then recommending supplements. Experts I talked to say they consider Conte's theories medical mumbo jumbo, but he consulted with dozens of top athletes, including Marion Jones; Amy Van Dyken, an Olympic champion swimmer; and Bill Romanowski, a linebacker in the N.F.L. Jason Giambi of the Yankees was also a client and also testified before the grand jury.

In an article that appeared last June, Bonds told Muscle and Fitness magazine: "I visit Balco every three to six months. They check my blood to make sure my levels are where they should be. Maybe I need to eat more broccoli than I normally do. Maybe my zinc and magnesium intakes need to increase."

Bob Ryan, a veteran Boston Globe sports columnist, is among the baseball devotees who want to believe all Bonds is taking is broccoli and vitamins. But with both Bonds and Sosa, the presumption of innocence he would like to grant them clashes with the accumulation of circumstantial evidence and his own common sense.

"I knew every baseball benchmark from the time I was 10 or 11 years old," Ryan says. "I knew 60, and I knew 61. I knew 714 (the former career home-run mark held by Babe Ruth). Stats frame who a player is. They're part of the romance of the game, the enjoyment."

Bonds, with 658 career home runs, could surpass Hank Aaron's all-time total of 755 in just two or three more seasons. If he does, what will it mean? Will it carry the romance of other cherished baseball records? "Bonds was a leadoff man who could run early in his career, and now he is this hulking slugger," Ryan says. "Sammy, same thing. You want to believe it's all due to weight training and nutrition, but you have these guys hitting 40 home runs, maximum, and then well into their careers, they're in the 60's and 70's. It doesn't happen."

But Ryan is not seeking much new information on this subject. "I'm afraid of what you're going to tell me next," he says at one point in our conversation. "I'm living in some sort of denial. I'm afraid to look under the rock."

The world Anti-Doping Agency, imperfect as it may be, is generally considered an improvement over the patchwork approach to drug enforcement that preceded it. Created in 1999 at the World Conference on Doping in Sport in Lausanne, Switzerland, the agency was intended to bring coherence to antidoping regulations and "harmonization" among all the different nations and sports bodies expected to enforce them. In theory, it is the ultimate authority on matters of drugs and sport -- looming over national Olympic committees and the national and international federations of all the individual sports and making it more difficult for those parochial interests to protect athletes caught doping.

W.A.D.A.'s medical committee devoted several years to compiling an impressively voluminous list of banned substances. But the role of W.A.D.A. and its president, Richard Pound, is mainly bureaucratic and political. W.A.D.A. can't slow science down -- or influence a culture that hungrily pursues human enhancements of all kinds.

"All of these issues are going to be moot in 20 or 30 years," says Paul Root Wolpe, a professor of psychiatry at Penn and the chief of bioethics at NASA. "We already are seeing a blurring of the line between foods and drugs, so-called nutraceuticals. In the future, it will be more common, accepted. We'll eat certain engineered foods to be sharp for a business meeting, to increase confidence, to enhance endurance before a race or competition."

Currently, in determining whether to put something on its banned list, W.A.D.A. considers whether a substance is performance enhancing, contrary to the spirit of sport or potentially dangerous to health. "If it meets two of the three criteria, we are likely to put it on the list," Pound says.

But the first two criteria are ambiguous. Steroids and EPO are clearly performance enhancing. But so might Gatorade be, if you believe its advertising and all the data on the "science of hydration" disseminated by the Gatorade Sports Science Institute. And plenty of sports drinks claim to do more than Gatorade. "You identify a line and draw it somewhere," Pound says. "Why is it the 100-meter dash and not the 97-meter dash? It just is."

Between Gatorade and anabolic steroids lie all those powders and pills and injectibles that elite athletes put into their bodies, in quantities and combinations that may enhance performance or may prove innocuous. In most cases, no one is quite sure.

Less open to interpretation is "potentially dangerous to health." Any medical or pseudo-medical activity that takes place underground or in the black market is, by definition, dangerous. Nearly everyone, regardless of how they feel about abortion, will agree that it's more dangerous when it occurs in a back alley. Steroid use, dicey in most situations, is certainly more so when it takes place in the dark.

So issues of health are the strongest rationale for W.A.D.A. and the whole antidoping effort: to protect athletes from their own worst instincts. (Though the sports world is selective about its concerns for athletes' health. Offensive lineman in the N.F.L. just keep on getting fatter. The typical career of a major-league pitcher usually involves the gradual deterioration of shoulder and elbow.) But safety is going to become less of an issue.

"Right now we have a crude way of enhancing muscle mass," Wolpe says. "Years from now we'll look back on it, and it will seem low tech. When it's all on the dining-room table, there will not be the same kind of health issues we are seeing now with the unregulated and illicit supplements and drugs."

What I learned during my visit to Lee Sweeney's lab at the University of Pennsylvania is that lifting his research for purposes of athletic enhancement is not from some sci-fi future. It's possible -- now.

Sweeney and his team know for sure they can build muscle mass and strength. Their next step as they try to determine if their methods are safe for humans will be to experiment on larger animals, most likely dogs with muscular dystrophy.

I asked Elisabeth Barton what would happen if some rogue nation or outlaw conglomerate of athletes asked her to disregard scientific prudence and create a human version of the mighty mice. Could she do it?

"Could I?" she answered. "Oh, yeah, it's easy. It's doable. It's a routine method that's published. Anyone who can clone a gene and work with cells could do it. It's not a mystery."

Behind her, Sweeney nodded his head in agreement. "It's not like growing a third arm or something," he said. "You could get there if you worked at it."

Sweeney said that once someone decided to use gene therapy to enhance performance, "you would not be limited to what I'm doing. You could change the endurance of the muscle or modulate the speed -- all the performance characteristics. All the biology is there. If someone said, 'Here's $10 million -- I want you to do everything you can think of in terms of sports,' you could get pretty imaginative."

To strengthen leg muscles for a sprinter, Sweeney said, he would "put the whole leg on bypass. I would isolate the leg and put in the virus through the blood. It would be more efficient than injections, which you would need a lot of because you're dealing with large muscles. But this is nothing a vascular surgeon couldn't do."

Could one already be doing it? "I don't know that it's not happening."

IGF-1 is already available on the Internet in ingestible form. It is advertised as a component of various powders and pills, and in this form it falls somewhere in that vast, murky area of legal, quasi-legal, black-market and plainly illegal substances for sale in the semiregulated supplement industry.

But Sweeney says that any nongenetic transfer of the protein would be ineffective -- it would not circulate in the blood in levels high enough to build muscle -- and unsafe, because to the extent that it does circulate, it would target nonskeletal muscle, including the heart. (The mighty mice have shown no signs of enlarged hearts or other organs and no sign at all that the IGF-1 is circulating in their bloodstreams.)

For the elite athlete, that would be one of the benefits of genetic IGF-1. It wouldn't circulate in the blood. It would be detectable only through a muscle biopsy. It took a long time for the world's athletes to agree to submit to blood tests; it's difficult to imagine them consenting to having investigatory needles stuck in their muscles.

W.A.D.A. invited geneticists and others involved in the latest medical research to a conference in 2002 on Long Island. The antidoping officials were (and still are) focused on the IGF-1 research at Penn, so Lee Sweeney was there. He listened as Richard Pound tried a very tough sell.

The W.A.D.A. president told the scientists that he certainly appreciated the work they were doing, knew that they approached it with single-minded dedication and understood full well that nothing was more important than seeking cures for dread diseases. He then talked about another "humanistic activity" that he said was already threatened by science of a certain kind -- the current science of performance enhancement -- and could be ruined by the misuse of their research. As they moved forward, Pound asked, could they somewhere keep in mind the interests of sport?

As Pound recalls, the initial responses he got were somewhat dismissive: "They said we work at the gene level. You can't really tell what was altered from what was there naturally."

Pound, a lawyer, then asked rhetorically: "What if I could assure the Nobel Prize in Medicine would be awarded to the person in this room who figured out how to make a test to determine if a competitor had been genetically enhanced? You could do it, right?"

Pound got an acknowledgment that detection might be possible with enough resources devoted to it.

Lee Sweeney generously consults with W.A.D.A. and other antidoping officials. He's sympathetic to their cause. He just says it's hopeless. "There will come a day when they just have to give up," he says. "It's maybe 20 years away, but it's coming."

There is a parallel from the past for the entire issue of performance-enhancing drugs, one tied to what was once another unwelcome substance in sports: money. Some casual followers of the Olympic movement may still not fully realize that nearly all of the participants are now paid professionals. There never was any big announcement that the cherished concept of amateurism -- athletes competing for the pure love of sport -- had been discarded. But over time, the changed reality has been accepted. Top athletes profiting from under-the-table payments? The public didn't care, and the ideal of amateurism expired, outdated and unenforceable.

One of the last things Pound said to me indicated that he knows, too, that W.A.D.A.'s mission has an expiration date pending. Maybe genetic enhancements really won't work for athletes, he speculated. "If you strengthen the muscle to three times its normal strength, what happens when you break out of the starting blocks? Do you rip the muscle right off the bone?"

Pound seemed to like the thought of this gruesome image. He paused, then extended the thought. "That would be nice if that happened," he said. "It would be self-regulating."

Copyright © 2002 Michael Sokolove