Heading out to work this morning for the first day back after the festive break. The weather had taken a turn for what it’s supposed to do over Christmas but always seems to come a bit later, just to make going back to the office that bit more exciting. Ice encasing the porch door, frost glistening off the wheelie bins, and pretty skiddy underfoot.

I turned the corner towards the tube station and there it was. Tripping towards me paying no heed to the ice was that most masochistic of creatures, not often sighted down our way.

Clad in the familiar combination of tiny shorts with a woolly hat and gloves, a head torch indicating just how unholy an hour he must have set out at (this could be easily seen despite not having binoculars with me, a fact I was grateful for given the shortness of those shorts).

The lesser-spotted marathon runner, on an early morning training run.

These quiet but determined creatures start to multiply at this time of year. They are revealed in the open more frequently and at increasingly unlikely times of the day and night during the winter months. You sometimes even see them right through Christmas, with the highest concentration starting to appear in January.

They will frequently leave shelter and remain outside for upwards of three hours at a time, surviving on little more than a brightly coloured isotonic drink and some small packs of a sticky, gelatinous substance not found in nature. Certainly not in that many flavours, anyway.

Typically this baffling behaviour comes to a head between the months of February and April, when thousands of them migrate to cities around the world – Tokyo, Rome, Brighton, London – to complete their final glorious display.

Often this display is complimented by outfits in various shades of brightly coloured lycra, sometimes with vests in tribal colours denoting which larger group or ‘club’ of these slightly mad creatures they each belong to.

The display basically consists of running for several hours. Really in a lot of cases, lots of hours. It’s as simple as that. Running for as long as it takes to complete 26.2 miles. Continuing to run without giving up, until they get to the finish line.

This is what they will have spent their winter dedicated to and preparing for, come rain, shine or frost. No excuses. They just put on a woolly hat and keep going.

After their final task is complete they are rewarded with a large piece of tin foil, a small piece of metal on a ribbon, and a huge sense of pride, achievement, and belonging to a truly unique gang.

And it’s this that will keep many of them coming back for more every year.

The sense of pride I mean, and maybe the small bit of metal. Not the large piece of tin foil.

That would be silly.

Good luck to all the Spring marathoners out there, I know there will be lots of you starting your plans this week as I have – London 2017 is on! I will be running it for Coram, the UK’s oldest children’s charity. If you fancy sponsoring me, you can do so here.