If the film Groundhog Day had never been made, I wonder what we performers would compare the Fringe experience to. After week two you hear someone mention Groundhog Day every day, which is in itself a bit like Groundhog Day. This is why they never made Groundhog Day 2: Bill Murray Notices How This Is Just Like The First Groundhog Day And Then Is Doomed To Repeat This Realisation Forever. Maybe they should. The kids love any excuse to use the word 'meta'.

I hate to say it, but with mere days to go before I board that train to Waverley, it feels like that already. Was it really four years ago that the Olympics were going on, and we were all at the Fringe getting drowned in the wettest August on record, but nobody could really enjoy it because Russia was tearing Georgia a new one in South Ossetia, and the UN couldn't do anything about it because Russia blocked any such suggestion at the UN? And now here we are, with rain forecast for the duration, and Russia letting Assad rip his own country a new one. And in the background, in the corners of bars, in the changing rooms of gyms; in the extremities of overcrowded, pant and sock-strewn sitting rooms, weightlifters gurn and people with salad strainers on their faces poke each other with bendy sticks. And we'll sit there on beer-puddled tables with sheaves of biro-scrawled paper, while huddles of people groan, or cheer, or say "Oooh! So close!" about something so removed from our insular Fringe world it might as well be happening in... well, Beijing.

Nothing else really matters once the Fringe starts. I'll care less than most, because I've never really understood sport. I guess it's one of those things like toilet sex or facial studs - if you have to ask people why they do it, you'll never really know. I realise this is swingeingly arrogant and, at the moment, possibly even blasphemous. But like most comedians I graduated to this art through the School of Being Picked Last for Everything, the College of Trying Not to be Punched and, finally, the University of Vanishing Up My Own Arse. I like to think of my first Fringe show as the graduation ceremony to all this. I'm now doing a PhD in Me.

Sport is essentially pointless. To a child who answers every question with another "But why?" there is no end to sport's line of enquiry. Look at him, trying to be the fastest man ever to have run 100 metres since the last man who did it four years ago! But why? What will he ever have to outrun for only 100 metres? Why 100 metres? Why are those people swimming? Why does anyone ever swim? Most aqueous obstacles can be walked around, unless you've jumped off a sinking ocean liner, in which case you will eventually drown without a life vest anyway. None of these skills are transferable. Machines do all these things better. Why get vascular women to throw cannonballs through the air? We have cannons for that. Cannons are really good at throwing steel balls through the air. We English didn't reduce Edinburgh Castle in 1573 with a battalion of vascular women.

Remember Jurassic Park II? Of course you don't. Nobody does. Near the beginning, and for no apparent narrative reason, Jeff Goldblum's daughter reveals she has been dropped from the gymnastics team even though she's really good. Later, she does a parallel bars thing where she kicks a velociraptor in the face. At this point I saw, briefly - fleetingly - a reason for a human being wanting to become a stone-faced, titless, friendless Romanian anorexic who has been robbed of a happy childhood. So that, in the event of a timeshift cataclysm or a DNA reanimation, they could - providing the final chase scene ends in a gymnasium - kick a velociraptor in the face.

Every four years we watch people who have starved themselves, tortured themselves, bank-rupted themselves, grown freakish deltoids, pecks and quads on themselves; denied themselves proper, useful jobs which might have contributed more than arrant jingoism to our dying nation, at huge expense to our dying nation. We watch them put themselves through hell and, in most cases, get cold, cloying defeat as a reward. And all because they were two hundredths of a second slower than some other devotee of self-mortification. I mean, what in God's name is the point of that? It's nothing but a carnival of cruelty.

Even if they win we'll remember them for all of two weeks. From then on their only function will be the autumn pasture of punditry; their lives a circular spiral into oblivion like a clapped-out teacher teaching wannabe teachers how to teach like a teacher at a teacher training college.

Yes, I know you disagree. I know that even sociologists and cynics see sport as an essential alternative to war, even when there's actual war on the other channel. Don't try to re-educate me. I just don't get it and I never will. I'm too busy trying to decide whether my show needs a Powerpoint presentation, and which obscure indie band I should choose for my walk-in music, and how to fit in this rape joke I've written that I think is perfectly okay, because it's a very feminist rape joke and therefore incredibly, impossibly important in the greater scheme of things, and 100 other things which, I'm absolutely sure, will dwell in the hearts of men, and the breasts of women, and the dreams of children, long after Jessica Ennis wins her 50th sponsorship deal for being passably doable. Honestly, what we comedians do up there is timeless and monumental. We're building Stonehenges of witty exposition. But you probably won't get to experience any of this brilliance because you'll be in a pub watching the bloody judo.

Just like you were four years ago.

Liam Mullone's show, A Land Fit For Fuckwits, is at Stand 4, 28 York Place, August 3-27 (not 13) at 3.30pm. There's a preview on August 2 at 2.20pm.