They walk funny, but they're not laughing

There are several images of the 30th Olympiad in London that will remain with us for life.

Michael Phelps standing atop the podium one last time or Usain Bolt taking photos of the crowd following his triumph in the 200 metres final are a couple.

Whatever your memory is, cherish it.

These memories are as personal for you as they are for the athletes.

There's an image seared into my brain which will live forever.

It was a four-and-a-half-hour sporting and emotional education that took place last Saturday night in the shadow of Buckingham Palace - the men's 50 kilometre race walk.

I had seen race walking before but never took more than a passing interest.

They were those skinny blokes, walking funny, trying not to run but for all the world looking like they were running, for hours and hours on end.

I knew they worked hard from seeing Craig Barrett complete endless laps of a circuit he had in Fairview Downs while flatting in the area.

Yet by the time my commentary stint ended just after midnight, my view of these athletes had been shattered and replaced by an immense amount respect, tinged with confusion.

When the gun cracked, 63 athletes set out on their Olympic odyssey - 51 would finish.

The first half was fairly uneventful, aside for the odd disqualification for technical infringements.

The first sign of what was to come was when a shot of Nenad Filipovic flashed up on the screen. The Croatian was lying on his back just to the side of the main straight, receiving medical treatment.

The next thing we see is Filipovic being carried away on a stretcher with an oxygen mask over his face.

That disturbing vision was followed by a series of images of Spain's Benjamin Sanchez.

Sanchez was well placed at the halfway point but as he went further into the race, the bigger the struggle.

Standing at the drinks station, the Spaniard was pouring water over his hips, stuffing a wet sponge down the front of the shorts before dousing himself with more H 2O.

The form of his stride, which was very precise through the first section of the race, was breaking down, as was the man himself.

And yet he continued on, battling physically and mentally in a display which was incredibly courageous yet just as harrowing to watch.

But Sanchez was not alone.

As the other athletes made it over the finish line, we saw them just collapse into the arms of officials.

As soon as one walker was taken away in a wheelchair, the officials were looking for another to take away the next athlete in need of medical attention.

And all the while, Benjamin Sanchez continued his slow plod to the finish line.

Finally after nearly four hours and 15 minutes of race walking, Sanchez made it to the finish. He stopped, made the sign of the cross, looked to the sky and stepped over the line.

The official results will tell us that Benjamin Sanchez, representing Spain, finished 50th in the men's 50-kilometre race walk at the London Olympics.

But the fact is he won, as did all the competitors who finished that day.

I will never understand what drove those men to push themselves like that and there's a part of me that actually doesn't want to know, such is the indelible impression it has left me with.

But in the future when asked what the toughest event at the Summer Olympics is, I will answer the 50-kilometre race walk - a strange, incomprehensible blend of endurance, technique, strategy, concentration and courage that shall be feted, not mocked.

- Nigel Yalden is a Waikato-based sports commentator for Newstalk ZB and Radio Sport.