By Fred Brenton BBC News website reporter

Finished at last: The training is over now Fred has crossed the line

Have you ever seen those mystics walking over hot coals in search of spiritual enlightenment?

It usually takes them about 10 seconds to skim over the burning rocks beneath their feet and then come out smiling at the other end feeling all good and holy.

Well I spent about five hours doing something very similar on Sunday but with more than a grimace than a grin.

Yep, I actually finished the Cardiff Marathon, despite all the online moans and groans, in a very respectable four hours and 45 minutes and actually quite enjoyed it despite the immense pain.

Don't get me wrong, I would be smiling right now - if I could - but it takes several muscles to smile, and every one I have at the moment is concentrating on keeping my eyes open.

And unlike the daredevils with the coals, my feet have felt like they've been burning up since about noon onwards.

You know when Jerry jams a match between Tom's toes and lights it up in those cartoons - it felt a bit like that but worse.

Don't ask him to do this just yet - it hurts too much

On top of that my legs and arms feel like lead, my head is as light as feather and my stomach is running on what must be empty.

Yep - this marathon malarkey is serious medical stuff and I don't think I've ever been more exhausted in my life.

But despite the physical ills of running 26.2 miles around the capital I do feel surprisingly good.

I didn't do this whole thing in search of reaching a higher plane but I am genuinely on a high of some sort.

I must be the warm glow of self-righteousness that I now have after finishing something that even some members of my close family doubted I would - despite all the training.

It's nice to proved right once in a while and to fly in the face of opinion and this must be what I'm feeling right now.

People's kind words

At more than one point I, too, doubted I would complete the course but you'd be surprised at what an effect random strangers shouting encouragement can have upon you.

It's amazing the skip you can get into your tired stride off the back of a few words of well-being thrown your way from the sidelines.

Kind people's words saved me from retirement more than once on Sunday and kept me going even when my mind, body and soul were screaming for me to put an end to my personal suffering.

So in signing off, I would just like to thank all the good people of Cardiff for their support and to say that I will more than likely be visiting them again next year.