'What are you looking to do it in?'

It's a completely innocent question from people taking an interest in how my training for the Greater Manchester Marathon is going.

However, it's not a question I can give a quick answer to. If only these people knew just how much I agonise over what time I'm going to get round in.

But I'm really trying not to let my finishing time be what defines whether I regard the race as a success or failure.

I understand it's the easiest gauge but, just like so many others training for an endurance event, I've put in so much time and energy into this. To merely let whether I get round in around the 3-30 mark wouldn't be fair to myself.

That doesn't mean I'm not going to get round as quickly as possible and I want to post a time that I can look back on and be proud of.

But to just look at someone's finishing time can dismiss a lot of the work and struggle – the 5.30am alarms, the three-plus hour runs, the constant fear of getting ill and missing a run, the tiredness, the guilt… the constant guilt that you're not giving enough of your time to your family.

MORE: Love running? Join the Run Anglia Facebook group hereTime is at an absolute premium in the Armstrong household at the moment especially with my wife, Alison, also in training for London.

She's got her own training demands to consider and she's also getting to the stage where she's thinking about what is a realistic finishing time.

She would love to go under four hours but, just over a year after having our son, Logan, she knows it would be silly to fixate on that goal. To get the training in required, get round and even finish strongly, should be regarded as a victory in itself…but we aren't always that kind to ourselves are we? She isn't anyway.

As you can imagine there is a lot of running talk in our household.

We both love it but it's safe to say we've had enough of the long runs especially at this stage.

But it's not forever and whenever one of us feels down or tired about our training the other will repeat the mantra 'we're nearly there…'

A lot of the hard work has been done by now and it's as much about keeping your mind in check than it is about getting the miles in.

The irony is that I know that a few days after Manchester I'll start to get itchy feet and miss the structure and focus that a marathon training block provides.

Nothing has focused my mind on training more than working towards a marathon for one main reason - it's scary.

If you don't get it right then it can become an absolute suffer-fest when even a couple of miles can feel like you're asking the impossible.

I've been there with the creeping sense of panic that descends.

That's why I've committed so much time and effort into my training, sometimes at the expense of things I'd rather be doing (like sleeping).

I need to build confidence that when the going gets really tough in the latter stages that I can handle it and not let my race fall to pieces as it so quickly can.

It's why after much deliberation with Neil Featherby we've decided to get one more long run in before Manchester, just two weeks before the event.

In an ideal world (what's that?) I would want an extra week to taper but we concluded I would get more out of one more long run and the information that could provide to settle upon what my target pace is going to be.

It's why I can't give a straight answer when people ask me what time I'm looking for.

It's also why I won't let my finish time be the only determining factor in whether Manchester is a success or failure.

Good luck to those running the Wymnondham 20 this weekend. If you're using it as a training run then remember to use it as such. Don't leave your best effort out there and leave yourself short for your main event. It's why I haven't signed up to it – I can't trust myself not to race!