The universe seems to be throwing message after message at me this past week.

First it was the very dusty pair of hiking boots I came across when I was tidying up the flat. Covered in cobwebs, they also had a woodlouse run out of them which is proof they haven’t been used for a very long time indeed.

Next up was an article in this month’s issue of ELLE which I read on the Ryanair flight to Barcelona where my younger brother lives.

‘What’s stopping you exercising?’ it asked on page 175. Time, I muttered under my breath before being told on the following page that this was a pathetic excuse for not pulling on my trainers and shaping up.

If that wasn’t enough, I pulled in £25 of sponsorship within minutes of putting my Virgin Money Giving page online last week.

I should have been thrilled. And I was. But deep down, I’m not sure I really expected anyone to sponsor me and probably thought I could call the whole thing off and slink quietly away without anyone noticing.

But now I can’t. Not when I’ve moved people to tears and they’re responding by stumping up way more than the £1 I was - and still am – appealing for.

So when I got to Barcelona, my plans for doing little besides sipping sangria, tucking into tapas and strolling around the shops got shelved pretty much instantly.

Having been made to feel guilty by a magazine, I decided to take action. Instead of getting a cab from the city’s Estaçio Nord to my brother’s flat in the heart of the Gothic quarter like everyone had told me to, I went on foot.

And I’m glad I did. It was only 1.8km and in less than twenty minutes, I saw the Arc de Triomf, walked along quaint streets and crossed Plaça Sant Jaume, home to Barcelona’s 14th century city hall and the Catalonian government building with a statue of St Jordi slaying a dragon on the balcony.

In fact, by the time I reached my brother’s front door I was feeling suitably chilled out and definitely in holiday mode. ‘Top floor,” he said, buzzing me up to his flat. ‘Sorry there’s no lift. See you in a sec’.

One hundred steep steps up a very narrow staircase later, I arrived. At that moment, the contrast between me and my brother couldn’t have been greater. While he was looking tanned and relaxed, my face was red with exertion. It was only after I’d downed two pint glasses of water that my heart rate returned to normal and I could wish him a happy birthday which was why I was there in the first place.

Then just as I was sinking into the sun lounger and admiring the view from his rooftop terrace – it doesn’t take me long to make myself at home – we had to head out again, this time to fill up the gas cylinder so we could all have hot showers in the morning.

Once we were back, I headed up to the flat first because my brother had to lug the now heavy gas cylinder all the way up the flight of stairs. He maintained that he would take ages and I should go on ahead. That we arrived at the same time says how blatantly unfit I was.

But by the end of my five-day stay in Barcelona, things had changed. I might not have been running up the stairs but I did walk up and down them at least six times a day without getting out of breath. And on the Monday before flying home, I inadvertently covered at least ten kilometres after losing my bearings on my way back down hilly Montjuic. Still, at least I got to see Passieg de Gracia, the city’s most elegant avenue which can be traced back to the Romans.

I was so zenned out after walking all day every day, that I vowed to go for two one-hour walks a day when I got back.

Needless to say, my good intentions haven’t yet been turned into reality. With nothing to distract me, I’d happily ditch the car and walk everywhere because the feel-good factor is too good to ignore. It’s easy to find the time when you’re on holiday though and don’t have to meet deadlines, plan lessons, study, do the food shop and juggle a million other commitments.

I’d rather go for a twenty-minute jog than a one-hour walk and if I do have a whole two hours spare, I prefer to spend it kayaking, the sport I loved as a teenager and have recently taken back up.

But I know I’m making excuses when, as ELLE continues to tell me, there are none to make, especially because me successfully walking 60km across the South Downs next May will make all the difference to Winston’s Wish and the bereaved children it helps.

And surely the whole aim of the challenge is to do something I wouldn’t normally do. What would be the point of putting in no effort in whatsoever and enjoying every single step I take?

So tomorrow I will set the alarm an hour earlier. And this time I won’t hit the snooze button and fall back to sleep.