Eliud Kipchoge and Brigid Kosgei were born to run marathons. Their childhood was spent at 2,500m altitude in Kenya's Great Rift Valley and now, with science and commerce at their feet, they are lopping chunks off the men's and women's world records.
Last Saturday, Kipchoge became the first human to run the 42.195km distance in under two hours.
The next morning, Kosgei took more than a minute off the 16-year-old women's marathon record by clocking 2hr 14 min 4 sec in Chicago.
His wasn't a race; more a contrived time trial.
Her's very definitely was a run against others, and against the weather, the course, and history.
They surely are renowned athletes from a remarkable part of Africa. I have run (plodded, to tell the truth) up the red dust trail at Eldoret where the great Kip Keino inspired Kenyans through his legacy. And I couldn't have greater respect for the simplicity, the child-like joy, of running with nature there.
However, when Kipchoge claimed his sub-two hour breakthrough as a mental achievement equivalent to Roger Bannister's sub-four minute mile, I beg to differ.
Again, I had the privilege of knowing Sir Roger personally. Running was his release from his calling as a neurologist, an Oxford scholar dedicated to seeking cures for central nervous system impairment.
As an amateur athlete, the four-minute mile intrigued him. He was convinced it was a mental rather than a physical barrier. And on a cold, windy, wet day in 1954, he set out with fellow former Oxford scholars to prove it.
He worked that morning in a London hospital and caught a lunchtime train to Oxford where in the evening he broke that barrier. He applied the science of the day by filing the spikes on his running shoes so that they would not clog up from the cinder track.
And yes he was paced, following Chris Chataway and Chris Brasher until with his slender long limbs and superior lung power he sped past them over the final 275 metres. Within 46 days, his record fell to an Australian, John Landy.
As Bannister believed all along, the limitation was mental.
Kipchoge's achievement is somewhat different. He is a millionaire several times over by winning more marathons as a full-time runner than anyone else.
But last Saturday was not a race. It was paid for by a British billionaire and by Nike whose vested interest was in the prototype running shoes made specifically for Kipchoge. Those shoes are an exclusive version (for now) of the one marketed from America to the runners' world.
Kosgei ran in similar shoes, and like club runners, pros and amateurs alike, this footwear is said to feel "like running on trampolines."
The claim is that the shoes increase even a basic runner's performance by four per cent. In Kipchoge's case, the carbon fibre plate was meant to reduce the load on calves and ankles, the foam to absorb and return energy applied to the ground.
Ah yes, the ground. A six-mile circuit in the Prater, the so-called "green lung of Vienna" was chosen because of its straight, flat terrain and the Austrian city's 10 degC temperature at this time of year.
Then there were the 41 pacemakers, themselves world-class runners, who took turns, seven at a time, to run in front of Kipchoge, fanned out in an aerodynamic arrowhead formation to deflect any wind resistance.
Also attendants to give him supplements and water at precise times so that he didn't have to break stride.
And the computer-generated green beam of light from a car in front of him, indicating to the precise split second timing he needed to maintain to break the two hours.
I may have forgotten some of the scientific support, may have overlooked the crowd amassed to encourage him around the circuit in the early morning that analysts assessed as the perfect time to make this run.
The IAAF is setting up a working group to consider the issues of technology assisting athletic performance. Kipchoge's run doesn't enter the record books because it was not a race against other athletes.
The appliance of science is nothing new in sports. Tennis players wield graphite rackets. F1 drivers race inside space-age technology.
And anybody who has been to a modern gymnasium works out on stuff that previous generations would never have believed.
The world around us changes. Full respect to Kipchoge as the outstanding runner of his time; but please don't compare the achievement to Bannister's Mile.