BioEd Online

What do you need in order to be a record breaker?

Sports experts agree that the single most important factor in creating a champion is genetic makeup: the possession of genes that impart an innate ability to stride, leap, burn energy efficiently or suck lots of oxygen from the air. "The great athletes are genuine statistical outliers... physiological freaks, if you will," says sports scientist Craig Sharp of Brunel University in Middlesex, UK.

On top of this, however, training and technique are vital. They allow athletes to sculpt muscles, for example, so that they burn less energy while achieving the same speeds as others. State-of-the-art technology can be essential, particularly in sports that rely on specialized equipment, such as tennis or pole vaulting. Chance also plays a part: cool temperatures or wind might add that extra push for a runner or long jumper.

Ultimately, a record-breaking performance depends on bringing all of these factors together on the right day. "It's the stars becoming aligned," says Lynn Millar, who studies physical therapy at Andrews University in Berrien Springs, Michigan.

Is winning 'all in the mind'?

Psychology is vital. Athletes need enormous focus and drive to win. Many people think that the main barrier to breaking the four-minute mile was a psychological one: once Roger Bannister did it in 1954, several others clocked sub-four-minute times shortly afterwards. Sometimes breaking a record involves taking a risk in an event, such as breaking from the pack with a full lap to go, and that takes a certain mindset.

How will we find or create the next generation of champion athletes?

The most likely way is to widen our search to find someone with a genetic make-up that allows him or her to surpass other athletes. When East African runners began competing internationally, for example, it became apparent that their light frames make them uniquely economical in their use of energy.

Once scientists have identified the genes that confer a genetic advantage in sport, athletes might also be screened to pick out the ones with most genetic potential. "There are all sorts of people out there, and we don't know what they can do," says exercise and sports scientist Carl Foster of the University of Wisconsin in La Crosse.

Because the rewards are growing and competition is becoming more intense, athletes are being driven more and more towards drugs to gain the edge. Experts predict that the next generation of champions will include many doped ones. They are particularly fearful of 'gene doping' in which athletes boost the performance of key genes. "Certain sections of the sports world watch developments such as this with a very keen eye," says Sharp.

Have we reached the limit of human performance?

No, but records are being broken by ever narrower margins. When statisticians plot how the best performance in a given event changes over time, they see the graph levelling off. And the shorter the event, the smaller are the slivers of time being shaved off. So although Paula Radcliffe has sliced whole seconds off the marathon world record, sprinters are improving by mere hundredths of a second.

Not every sport can be accurately measured, of course. Running and jumping can be quantified with stick or stopwatch, but football and tennis performances are much harder to gauge.

Will we ever reach an absolute limit?

Theoretically, an absolute limit to how far or fast the human body can go does exist, but "where it is we don't know", says Millar. Perhaps the only way we can recognize the ultimate performance will be retrospectively, after a record has stood for years.

Some experts have tried to calculate the absolute limit of performance. They take the highest value for each crucial physiological factor ever recorded in an athlete, such as the maximum oxygen uptake, the greatest efficiency with which energy is burned and the best stamina. Then they figure out how fast someone might go if these were all combined in one body.

By these calculations, we may one day see a sub-two-hour marathon or even a three-and-a-half-minute mile. But the probability of finding someone with these exceptional abilities is pretty low.

In future, will athletes simply test their limits in new ways?

As records become harder and harder to break, we may start comparing athletes by other standards, such as the number of gold medals or their performance over time. Lance Armstrong's six consecutive wins in the Tour de France, for example, may never be surpassed. "The élite might be defined by how many times they win," says Millar.

Athletes might also invent new sports to test themselves. The emergence of the triathlon in the 1970s was fuelled by runners, swimmers and cyclists looking for a new challenge; it made its début as an Olympic event in 2000.