Last Night's Television - Russell Brand: Skinned, Channel 4; Robson Green's Wild Swimming Adventure, ITV1

Take a likeable minor television celebrity, a random location, an offbeat activity, affix the word "adventure" to the title, and voilà: two hours' worth of prime-time programming. Hence, Stephen Tompkinson's African Balloon Adventure, Robson Green's Wild Swimming Adventure, and Adam Woodyatt's Galashiels Spelunking Adventure (I made the last one up). Anyway, ITV1 is fond of the format, and of Robson Green. Thus, Robson Green's Wild Swimming Adventure – that one was real – which began with a dream sequence, of the young Green trotting through a pastoral idyll, freshwater stream and all.

Green has always been drawn to water, he explained as he revisited Seaton Burn, where he, "Snadge" and "Bananas" used to swim as children. (He didn't clarify whether Snadge and Bananas were siblings, friends or family pets.) His miner father, whom he idolised, used to chuck him into the North Sea in his Y-fronts. And since Green Sr's recent passing, Green Jr had decided to swim to Holy Island, in their native North-east, as a tribute of sorts. We'll have to wait until next week to find out whether he made it.

Green is a strong amateur swimmer, but there's a big difference between a few lengths of the local indoor pool and an endurance swim through bone-chilling open sea. So, to prepare himself for the challenge, he took a tour of the country's various wild-water swimming options, from a lido in Plymouth, to Britain's oldest lake swimming club at Henleaze in Bristol, to a moonlit hot tub in the company of the Outdoor Swimming Society's comely founder, Kate Rew. Along the way, he showed no compunction about changing into his "budgie-smugglers" in front of various middle-aged women, who had evidently been told to look excited by the prospect.

In fact, the whole thing seemed a little too contrived at times. In one particularly implausible sequence – fortuitously filmed from multiple angles, including a helicopter – Green had to be "rescued" by the local river police after taking an impromptu dip in the Tyne. What with all the actorly romanticising of his personal journey, it was hard to separate the self-indulgent performer from the real person. His fellow wild swimmers were often charming eccentrics, well worth a few minutes more screen time, but instead the show began to feel like a strange, slightly corny ego trip.

Until, that is, the arrival of "human polar bear" Lewis Pugh, the man who swam the North Pole in 2007 and lost all feeling in his fingers for four months as a result. Pugh accompanied Green for a swim in Snowdonia's Llyn Llydaw, the coldest lake in Britain, and not only knocked all the ego out of him, but also enlivened the programme, wresting control of the narrative from its presenter. When Green emerged from the 8C water, his head spun, his legs gave way beneath him and he had to be swaddled and carried to a warm waiting Range Rover. The impervious Pugh, on the other hand, strode happily from the lake in his budgie-smugglers.

There was no danger whatsoever of anyone wresting control of Russell Brand: Skinned from its star, even though the second half of the title referred to Frank Skinner, whose sit-down interview with Brand formed the spine of this shapeless and curiously unrevealing documentary. Or at least it seemed unrevealing, because so much of Brand's life comes pre-revealed. Unfortunately for the programme-makers, their subject has built his stand-up career on confessional routines, so even when he was describing his most private thoughts to his fellow comedian, I felt like I'd heard it all before.

Still, neither man is ever less than engaging, especially when they're talking about themselves. Brand, much of whose recent Scandalous tour revolves around so-called Sachsgate, spoke intelligently about the affair. Clear-eyed when it comes to his own mistakes, he also argued convincingly that they were amplified by the context of the disputed BBC licence fee, Jonathan Ross's salary, and the hammed-up outrage of the press.

The most interesting moments of their conversation came when Skinner paralleled Brand's experiences with his own comparatively sedate career. Skinner admitted to having "done a lot of groupie-ing" in his time, but was troubled by the blot such behaviour might have left on his moral copybook. Brand agreed, but often, he said, he's simply overcome by the "oestrogen-filled mist" that descends on his gigs. He created his womanising, Byronic goth persona, he confessed, partly as a substitute for the drugs and alcohol that once sustained him. Now that it's brought him the fame he craved, he's stuck with it. "My personality does not work without fame," he joked. "Without fame, this haircut just looks like mental illness."

Skinner also praised Brand for having – with his distinctive estuary eloquence – made it cool to be articulate, a fantastic compliment from a comedian who'll probably always be associated with mid-Nineties laddism, which sadly had the opposite effect. At one point, Brand went into lyrical detail about his ritual, pre-gig poo, describing it as a physical and spiritual cleansing that prepares him to meet his adoring public. Hmm, Skinner replied, "Most comedians just call that 'the comedy shit'."