Sport on TV: Surely it's time for Crackers to put the shackles on himself

Former Olympic rower James Cracknell appears on TV so often these days that we must be seeing more of him than his wife and young family do. Hot on the heels of his three endurance challenges on the Discovery Channel – six back-to-back marathons in the Sahara desert, getting across the United States inside 18 days (and almost getting killed in the process) and "ultra-cycling" 430 miles through the Canadian tundra – he popped up again to tell the tale of his hero in Shackleton's South with James Cracknell (Discovery, Thursday). According to JC (not to be confused with someone of the same initials who sacrificed himself for the good of mankind rather than the sheer hell of it), "It's a tale of terrible hardships, bitter cold and exhaustion". You can see why it would appeal to him.

Crackers plays down his own achievements – unlike old Sir Ernest, he did get to the South Pole – but he can't help going on about himself. Yet those polar expeditions at the turn of the 20th Century have not been devalued by the likes of Crackpot and Co. Those old explorers had no satellite technology; in fact they had no communication at all with the outside world. But for Crackshot you sense that Shackleton's escape route sounds like some glorious triathlon: sail 800 miles across the roughest seas in the world, then hike 33 miles across a mountain range, shooting a few penguins along the way.

Perhaps the most startling aspect of this old story is the film shot by Frank Hurley. His camera is perched on the ice just in front of the Endurance's hull as it tries to smash its way through the floes, then we see the masts snap and the ship disintegrate as the party trudges off into the void. We watch them racing dogsleds and playing football while they were stuck in the ice for months on end. But despite the deprivations, there's no swearing into the camera. They would probably just have said: "We're taking it one step at a time."

As if there wasn't enough to worry about regarding Crackedmirror, now we see him revelling in the story of one of Britain's heroic failures. After two Olympic gold medals and several lifetimes – in cat's terms – of being a winner, now he is eulogising that British speciality, the plucky loser.

He delights in the anecdote of how Shackleton gave one of his men his last biscuit to save him from starvation. It's time for Crackhead to admire bravery from afar rather than keep putting himself on the line. He does have an alarming tendency to take the biscuit, and his status as a jammy dodger of misfortune seems to be increasingly at risk.

* The "three wise men", as Jeff Stelling called them, were in the studio for the second instalment of Manchester United v Chelsea (Sky Sports 1, Tuesday) but Christmas had not come early. Graeme Souness remarked that United were now a team who knew how to win, Ray Wilkins opined "You've got to defend like a defender" and Jamie Redknapp looked forward to his Thomson holiday. It took Ryan Giggs to come up with the wisdom: "They needed to score, and we just knew that we needed to try and score as well." There it is, 20 years of experience at the top level distilled into one sentence. A nation awaits the old man's move into the pundit's chair, where there will be plenty more dribbling amid all the drivelling.