Limits of endurance as marathon stars run out of time

PARIS: The Olympic motto is "Faster, Higher, Stronger", but what if we have reached the limits of the human body?

Some scientists have warned that when it comes to running -- from sprints to marathons -- the era of breaking records may be coming to an end.

That is, unless the next athletic evolution is artificial and it is doping, rather than human exertion, that breaches the next barriers.

Only one world record was broken at this year's athletics world championships in London, in the newly-recognised women's 50km race walk.

And at the 2016 Rio Olympics, just two running world records were bested -- South Africa's Wayde van Niekerk in the 400metre men's event and Ethiopia's Almaz Ayana in the women's 10,000m.

After the great advances of the 20th century, "the rate of improvement is approaching zero for the majority of athletic trials," said Marc Andy, a researcher at France's Institute of Sport Biomedical Research and Epidemiology (IRMES).

In 2007, the institute analysed the history of Olympic records since the modern Games began in 1896 and calculated that athletes have reached 99 percent of what is possible within the limits of natural human physiology.

The most recent near breakthrough in the gruelling marathon occurred in May when Kenya's Eliud Kipchoge came agonisingly close to sporting immortality, nearly running the first sub two-hour marathon.

He missed the mythical mark by just 25 seconds.

But the race conditions at the Nikesponsored event were so favourable -Kipchoge ran behind a six-man pacesetting team and was trailed by a time-keeping vehicle on a racing circuit in Monza, Italy -- that the time was not recognised by the International Association of Athletics Federations (IAAF).

Fellow Kenyan Dennis Kimetto remains the world record holder for his 2:02:57 run in 2014. - Imagining the perfect runner Coaches and scientists have long tried to figure out the optimal performance conditions for running the classic marathon distance of 42.195 kilometres (26.2 miles).

Beyond the ideal temperature -- around 12 degrees Celsius (53 degrees Fahrenheit) -- and the runner being small, "there are dozens of factors at play, from body type to physiological and biomechanical criteria," said Pierre Sallet, a performance expert from Athletes for Transparency, an organisation that promotes integrity in sport.

"How are we going to identify these parameters in these categories? How will we manage nutrition and altitude training as well as maximising form and energy to arrive on the day in the optimal psychological and physical condition?" Sallet asked.

Beyond environment and body shape, "three major physiological parameters come into play in marathons," Vincent Pialoux, deputy head of Lyon's Inter-University Laboratory of Human Movement Biology, told AFP.

"Endurance, the ability to create energy using oxygen," which is measured by a runner's VO2 max (Maximum Oxygen Uptake Capacity), and "motor efficiency", the body's ability to save energy, Pialoux said. - AFP