Unmasking Ironman

I have long suspected that my good friend Paul Bennett, a mild-mannered wizened professor of psychobabble, working deep in the dark and dusty catacombs of the almost Unseen University in deepest dusty South Wales (Swansea) was other than he seemed.
There had long been reports of his connection to the Ironman. He would often rush off around the world to swim, run, bike and rescue young maidens. This was no ordinary professor.
He and his long suffering wife Gill stayed with us last week. I watched for signs of his superpowers. They were well hidden. Allowing me to hammer him at snooker was clearly meant to misdirect me. His hobbling gait whilst using a walking stick; likewise. Their camouflage as local musicians was surprisingly good.

To be fair, he had not long undergone major surgery upon his knee, having had part of it replaced.
Would this stop him rescuing young maidens? I thought not.
He soon became restless of this charade, and zoomed off to the Pyrénées to take part in a local pushbike ride, a formidable 100 miles long ride going over 5 mountains. This would surely force him to show his true alter ego.
We followed cautiously at a safe distance (of about 6 hours) and hid ourselves upon a remote mountain.

To get there, we had passed through the clouds themselves, to gain a breathtaking view.
The first riders appeared...

...barely beating the clouds rising behind them. Would we recognise our quarry? Was this him?

Disguised as a mere human? I think not. Anyway, after manipulating his knee I found it decidedly in-bionic.
Time dragged on, the clouds crept upwards...

Hours passed. Still no sign of our superhero. Then I spotted an unusual bottom...

Surely that knee was artificial? Was this the Ironman himself?

As I approached him to finally unmask this saviour of young maidens, the clouds enveloped us...

I was undone.
After doing myself up, my phone started to vibrate. A small distant wizened voice escaped it wheezing "Help me, I cannot go on!"
We rushed to the bottom of the mountain to find Paul's bike slumped to one side, and Paul himself in an apparent state of extreme exhaustion. Another charade of course. I was now more sure than ever of the secret identity of Ironman.
But who was Paul Bennett?