Three hours, forty-five minutes and fourteen seconds

Maybe your brother's running his first marathon. Maybe you're terribly excited about it. Maybe some of the finest athletes in the world will be running right past the spot where you're standing. You love athletes. Maybe you and the city in which you live, whose future together is far from certain, what with your capacity for antagonism and mutual recrimination, will be having a really good day. This, then, would be the perfect time for you to leave the battery for your camera at home in the charger, where you'd remembered to put it the night before, and head out for the day with an empty, powerless camera in your bag, thus surrendering yourself to the inferior photographic skills of your mobile phone.

Excellent. Well done on that, Jones.

Young Miss Jones the Elder played the technology slightly better on Sunday, stationed in front of the computer at home like a pre-teen Uhura, carefully monitoring the digi-chat between the magic timing chip attached to her father's shoe and the internet, and reporting back to the rest of the family at their stations around the course.

Remember when I said I love athletes? I love athletes. While I was waiting to shout enthusiastic non-sequiturs at my brother at the 11-mile marker, I saw the elite men run past some time before him. At least, I think they were running. I couldn't swear to it. Pretty much what happened, I think, as it seemed to me, is that the rest of the world stopped and held its breath, and they floated past in a state of serene composure and physical perfection. It may be that I became incrementally a better person for seeing them, but I wasn't moved to buy a composter on the way home, so maybe the effect wasn't that dramatic.

This kind of thing has happened to me once before, about 12 years ago, on my only visit to Wimbledon (the tennis tournament, not the suburb – although actually, yes, both). We had seats on court number one, where Pete Sampras was playing. My friend was on Centre Court, thrilling to the lawn gymnastics of Becker (I think – it may have been Agassi), so I was sweating pure resentment when 'Pistol' Pete and his fuss-free competence walked on to the court. And then he started playing. That shut me up. 'You know that thing your soul rattles around in all day, the thing with the arms and the legs and the all-over skin?' Pete Sampras imaginarily said to me, in my seat far back in the stands. (Imaginarily, Pete Sampras has a really loud voice. Also, imaginarily, 'imaginarily' is an OK word to use.) 'Well, this is how it really works.'

In two years, London will be full of incredible people like this, and if you don't think this is very exciting you either a) don't live in London or b) would not endear yourself to me at a dinner party if this subject came up in conversation, causing me to sulk through dessert, snapping at accusations I was 'quiet this evening', and lie my way out of attending subsequent dinner parties I knew you would also be attending.

Anyway, at some point between the elite athletes and my brother (which is not such a big distance as you might think, not at 11 miles in any case) were the brilliant but mortal. One of them fell right in front of me, slipping over in the wet, his skin rasping across the tarmac. It was awful. No one knew what to do as he hauled himself up, furious and sore. The terror of saying something idiotic, so insultingly inane and unhelpful was paralysing. The very people who you'd think might have been up to the job, four St John Ambulance persons, remained rooted to the spot, dumbly brandishing a giant tub of Vaseline. Perhaps they are schooled not to approach an elite athlete in peril, in case they set about their finely-tuned muscles with excess enthusiasm and too-heavy hands. I hope that's the reason. I don't know what to say about them if it's not.

It feels hollow and all sorts of wrong to shout 'You can do it!' to someone who probably can, but not the way they want to, when you know that that difference means everything. I felt a bit like this afterwards with my brother, who did brilliantly but not brilliantly enough for him. I am counting on the attrition of congratulations and impressed faces he encounters over the next few weeks to convince him otherwise.