I wake up at half five in the morning for some reason, probably because the sun’s shining through my curtains, spilling warm yellow light on my face. On a whim, I decide to go for a run. I throw on my ancient leggings and a T-shirt, and rummage under the bed until I find my trainers. They’re a bit battered, but they’ll do. I leave my phone behind, because I need to clear my head and stopping to check Instagram every five minutes isn’t going to do that. I tie my hair up in a high ponytail that swishes as I walk.

I set off at a gentle jog from our place, feeling quite dynamic. That lasts until I hit the end of Albany Road, by which time my lungs feel like two exploding balloons in my chest. I stop for a moment, hands on my knees, doubled over and wheezing. God, I’m unfit.

But there’s something quite nice about being out in London at this time of the morning with no phone and nothing to do but take in the sights. I run along towards Holland Park where the pavements widen and the houses are gleaming white, the railings shiny black and the cars outside are massive brand-new Range Rovers. It gets a bit easier, somehow, as I keep going. And then I circle back, heading up Portobello Road, which is a hive of activity already. The stallholders are clanking bits of metal and laughing as they assemble their stalls. Boxes of fruit and veg and huge buckets of flowers spill out everywhere, echoing the rainbow colours of the buildings, and I feel a lovely glow of happiness and love for this amazing place I get to call home. This must be the runner’s high they talk about – or maybe I’m just delirious.

‘Is this a mirage?’ Rob says when he opens the door, before bursting out laughing.

‘Shut up, you,’ I say, collapsing in a heap on the bottom stair.

‘I’m only kidding,’ he says. ‘D’you want a drink? Looks like you need one.’

I nod, gratefully. Once I’ve drunk an espresso and my breathing has returned to almost normal, I stand up and catch a glimpse of myself in the hall mirror. In my head I’ve looked cute and sporty, my hair swishing back and forth as I jog along the streets of Notting Hill. The reality is distinctly less glamorous. My ponytail has slipped to one side, my face is an alarming brick-red colour, and I have two half-moons of sweat under each arm.

‘If you ever want a running partner,’ Rob says, in his gruff Scottish voice, ‘just ask. I did the marathon a couple of years ago.’