Sport on TV: The bare-faced cheek of the man with no clothes

You have to admire the man's naked ambition. Well, there's not much else to look at, to be honest. Mark Roberts from Liverpool was on some kind of winning streak: 517 times he had run around in public in the nude. Streak! The man who can't keep his clothes on (Channel 4, Thursday) followed him as he planned one final exhibition. We never get to see streakers on TV any more; the cameras always turn away, since it's regarded as encouraging publicity-seekers. But there are quite a lot of those on our screens in these days of reality programming. At least they keep their clothes on, most of the time.

We also see Roberts going for job interviews, because he has a lot of debts to pay off. "The last time I wore this suit, I was on trial in Texas after the Super Bowl," he admits, assuming the mantle – when clothing is permitted – of the stereotypical Scouser. That was the streak that made him famous, his antics as a stripping referee being watched by 130 million people.

He keeps his preoccupation under his hat at the job interview – rather as the policeman kept Erica Roe's breasts under his helmet at Twickenham in 1992. "Are you a team player?" they ask. "I always work around teams," he replies.

It all began at the Hong Kong Sevens in 1992, when he arrived on a one-way ticket with £30 in his pocket and ran the length of the field to score a try against the All Blacks. Presumably he thought he had more of a chance if there were only seven of them instead of 15.

Some three years later he was offered sponsorship by a betting company, and went on to streak in more than 20 countries before the deal came to an end in 2007.

What motivates him to bare all? He shows no interest in the sports he targets but the occasion provides the adrenaline rush he craves, just as it does for the fans. "I go and do a streak and I get a big buzz out of that for weeks afterwards," he explains. "I run naked to make a point, laugh at life. It's all about going against the grain." Frankly that sounds likely to cause some painful splinters.

As his assistant Gary points out, he does have respect for the sports and always times it so he doesn't interrupt play. And Gary should know about Mark's sense of decency; at the funeral of Gary's mother it was a case of "It's what she would have liked" as he stripped off and danced on top of Gary's brother's van. She would have turned in her grave, except she hadn't got there yet.

He has fallen on hard times since the sponsorship ran out. "People have been in touch about a book, possibly a film," he says. "There's even a guy been in touch about a clothes line and it's definitely going to happen, one million per cent." It's hard to imagine a line of clothing connected to streaking; you can see through a scam like that.

And so to the final exposure. He locks his mates in the pub with snakebites and black until they come up with an idea. Deliciously, someone suggests: "It's short notice but the [US] presidential elections are in a fortnight." Yet in a clear sign of the times they settle on the final of X Factor, but he doesn't go through with it, claiming his three children would be, like: "Whatever you do, Dad, not X Factor." It makes this wistful programme all rather pointless. If he had chosen Britain's Got Talent, he might have won it.