FOR more than 100 years, athletes have striven to complete the marathon in less than two hours. Now scientists believe that advances in genetics could lead to a runner completing the 26.22mile course in 90 minutes.

After a series of laboratory breakthroughs they claim that bio-engineering techniques could be used to create a superhuman long-distance runner.

The scientists claim that modifying the human genome could, in theory, increase the size of an athlete’s heart, boost the number of red blood cells supplying the body with oxygen and increase the endurance of specific muscles by up to 10%.

It is widely believed that, without genetic help, athletes are coming close to their physiological limits, despite increasingly sophisticated diets and training regimes. The prospect of superhuman athletes – and other genetically modified sports stars – could allow competition to thrive again.

French academics have claimed that no new sporting world records will be set beyond 2060 as athletes are now using 99% of their physical capacity compared with the 75% used by competitors at the first modern Olympics in 1896.

The possibility of the 90-minute marathon was set out yesterday by Henning Wackerhage, an expert in muscle energy metabolism, at a conference in London hosted by the Royal Society of Medicine.

Wackerhage, a lecturer at Aberdeen University and a former member of the German national triathlon team, pointed to DNA changes that have been introduced into laboratory animals. A “supermouse” at Case Western Reserve University in Cleveland, Ohio, has been bred to store sugar more efficiently, allowing it to outrun its rivals.

In other cases, mice have been bred with stronger and larger hearts, almost double the number of red blood cells flowing through the body and with “slow twitch” muscle fibres that improve endurance. If such a genetic change were to be repeated in humans it would allow energy to be delivered to thigh muscles more rapidly.

Wackerhage said: “There has been a raft of genetic developments, each of which has significantly increased performance. If these were combined in a human the boost to athletic ability would be phenomenal.”

Elite athletes usually display some enhanced physical attributes, but genetic modification of an embryo could put an athlete in a different league.

Paula Radcliffe, who holds the women’s marathon world record of 2hr 15min 25sec, is said to have a much bigger than average heart. She regularly trains at high altitude to increase her red blood-cell count. However, she was forced to pull out of the race at the Athens Olympics in 2004, claiming that she was “glycogen-defeated” – in other words, her body was running out of sugar.

The Ethiopian Haile Gebrselassie, who holds the men’s marathon world record of 2hr 4min 26sec, is regarded as having rare lung capacity, and muscle fibres perfectly designed for speed and stamina. Yet he has pulled out of the Beijing Olympics because of concerns about pollution.

While many believe Wackerhage’s claim is plausible, Matthew Lancaster, a cardiovascular researcher at Leeds University’s school of sport, said the whole body, not just the heart, may have to be improved. “By increasing the performance of the heart you create a cascading effect where all the other organs have to be modified to cope with the extra pressure,” he said.

Wackerhage admitted that a superhuman marathon runner was merely theoretical and genetic engineering to boost performance “will result in serious complications or death”.

China's dismay

THE Chinese ambassador has said demonstrations against the carrying of the Olympic flame through London had damaged her people’s views of the “gentlemanship” of Britain.

Fu Ying said the “violent” demonstrators during the event last Sunday had reduced young Chinese athletes taking part to tears and caused them to question whether Britain could be the same country that “nourished Shakespeare and Dickens”.

Fu also warned that, as a result of the demonstrations in London, Paris, San Francisco and elsewhere, many young Chinese were reconsidering their “romantic views about the West”.

She added: “In China the western media needs to make an effort to earn respect. Of those who protested loudly, many have probably not seen Tibet.”

Study on genetic modifications of how sugar is stored in the body

More information on London marathon

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