Marathons – Deciding Your Target Time

‘Why have you chosen that time?’ This is a question I often ask people when we discuss their marathon target finishing time. I get a number of varied replies such as:

  • Well I did xx.xx last year so thought I’d go for this
  • It’s only x.xx pace isn’t it
  • Don’t know really but should be doable
  • I need to do that for a Good For Age/Qualifying Time
  • My half marathon time is xx.xx so I can do this

Realistically, only the last answer is reasonably sensible and even then it depends on when their half marathon was run.

So many people just pick a finishing time or go for the nearest round number to the pace they usually run.

Now there is no actual science to predicting finishing times, it is important that people are realistic. If you are running a 16 week training programme there are so many things that can go wrong, or life gets in the way. Injury, illness, work and family commitments all get in the way at some point.

Let me discuss the answers from above one at a time to see if I can give reasons as to why these may not be sensible.


Well I did xx.xx last year so thought I’d go for this

Well done on last year. Are you better than you were last year? How has your training gone so far?

Realistically, to be faster than last year you need to start your marathon training with a better base level of fitness and speed that you had a year previous. If you are not as fit or fast, what makes you think you can run a faster marathon? You also need to change what you did the previous year. Not necessarily by much, but doing exactly the same is likely to get the same result.


It’s only x.xx pace isn’t it

Correct. How far can you comfortably run at that pace for at present? If they can currently run 5 or 6 miles comfortably at their target pace at the beginning of their training, then it is possible to run a marathon at that pace. It is then a case of having the training plan in place that will allow progression of the marathon pace miles to ensure that come race day, marathon pace feels comfortable for the majority of the race.


Don’t know really but should be doable

What makes you think you can do it if you ‘don’t really know’? Why is it doable? How many miles are you capable of at that pace at the moment?

So many questions that will get you thinking about whether you need to actually keep your mind open and choose a target closer to the race day.


I need to do that for a Good For Age/Qualifying Time

Once again, can you run at your target pace for a few miles at the beginning of your training plan? I have seen quite a few people chasing a Good For Age time in order to get in to the London Marathon, but so few actually know how they are going to get there. It is often a case of download a training plan for your target time and off you go, even though you are not up to the starting mileage or paces of the plan when you begin.


My half marathon time is xx.xx so I can do this

Now if the half marathon has been ran recently, and training has gone well since, this is a better indicator of fitness and prospects of achieving than the others. Most prediction calculators work on an average of multiplying your half marathon time by 2.22. The quicker you are (under 3 hours) you can get away with averages of 2.1 times your half marathon time. Anything over 5 hours and you are better multiplying your half marathon time by 2.4. If by doing these sums, your prediction is in line with your target then a good plan will give you the required long runs to ensure you have the endurance to convert your half time to a full marathon.


Keeping an open mind through training

My best advice is to have a rough idea of your target. This idea has to be realistic and based on what your pre-training training has shown you are capable of. However, be prepared for the initial target to change as you go through your training. You will be better placed around 4-6 weeks before your race to see how your training has progressed and if you are behind, on target, or even ahead of your original target. You can then focus on that pace for the remainder of your training to ensure you are in the best physical and mental shape for race day.


Variable Targets

You also need more than one target. Try to have the following:

A-Target – This is why you have done the training, the reason you are going to go all out for. It is just on your limit and will be either a new PB, Good For Age place, or, more commonly, a round number (sub-3.30, etc)

B-Target – This is an outcome that you will still be extremely happy of, even though it is not your perfect outcome. This is usually set at 5-15 minutes slower than you’re A-Target. The slower you’re A-Target the bigger the gap.

C-Target – This is your ‘acceptable’ outcome. One that you will be disappointed with on the day but you will be comfortable with the final outcome once it has sunk in.


The reasons for having these three targets are that during a marathon there are so many variables that are beyond your control that could affect your result. Such things as the weather being hotter or windier than usual, getting caught up behind slower runners (especially at the larger marathons), having an upset stomach or needing a toilet stop.

The overriding message is be sensible, be realistic, know what you are capable of at this moment in time and most important, have a good flexible training plan that suits your lifestyle, your capabilities and your target.


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Martin Hulbert

Personal Trainer & Running Coach Leicestershire