How Long Does It Take To Train For A Marathon?

Running a marathon is a serious personal challenge, and your success depends a lot on how much marathon training time you have invested in the months leading up to the big day.

But how long does it actually take to train for a marathon?


It all depends on your base running fitness level, as we’ll explore. However, there are other factors – such as injury avoidance and the rate at which you ramp up your mileage.

Most marathon training plans are 12 to 20 weeks. These timings assume that you are starting with a decent base of running fitness, from which to build on. An example of a base of running fitness would be running around 20 miles per week for 9 to 12 months, before committing to the marathon training plan. If you begin a marathon training plan with little or no recent running experience, you are inviting the risk of injury early on.

The longer you give yourself to train for your marathon, the better your chances of success.

By success, I mean:

  • avoiding injury due to ramping up your training mileage too quickly;
  • avoiding burn-out and running fatigue;
  • scaling up your training in a manageable, controlled fashion;
  • completing the marathon relatively comfortably.

Many people commit to a marathon without giving themselves sufficient time to train. What happens to them? If they make it through training without getting injured or de-motivated and make it to the marathon start line, they’ll probably get off to a good start. But at some point, they’ll get too tired to continue running – and have to walk. Or they’ll get injured, or completely fatigued – and have to pull out. So the key to marathon success is giving yourself enough time to scale up your training incrementally.


Start Shorter

Going from zero to 26.2 miles is ambitious. If you are serious about your marathon attempt, you might want to view it as a final goal with a few steps in-between. This means you should seek out 5k and 10k runs initially. A half marathon is a great event to build into your actual marathon training schedule and gives you a yardstick into how you’re doing.

But – the leap from half to full marathon isn’t an easy one. Many people with a good baseline of fitness can complete a half marathon in a few weeks of training. A full marathon, on the other hand, requires a lot of dedication to increasing your baseline stamina.


How Do I Assess my Base Running Fitness?

It all comes down to your running fitness level when you begin your marathon training. Ideally, you should already be running 20-30km/week over 3-5 runs, before embarking on a 3-5 month marathon training plan. If you’re not at this level yet, you should invest a few extra months in building up your base to this level.

Here are four ‘readiness’ categories to give you an idea of how long you should budget for marathon training.

Starting with the most-prepared:

 1. Already running 25-30km+ per week. Someone at this level can go straight into a 3-5 month marathon training plan.

2. Running once or twice a week; can run 10km without stopping. Someone at this level should spend 2-3 months building up their base running level before embarking on a 3-5 month marathon training plan. This means spending 5 – 8 months in total in training. Remember to incorporate some half marathons and local races into your training.

3. Not an active runner, but fit and healthy through other sports. Someone who is not typically a runner, but has a good base cardio fitness through other activities will want to spend 4-7 months building up their running base fitness before embarking on the 3-5 month marathon training plan. This means spending 7-12 months in total in training. They should look to start with local 5k and 10k events and get a half marathon onto their training schedule a few months before the actual marathon.

4An inactive person. If you’re someone who has done minimal running and doesn’t exercise regularly at the moment, then an excellent goal is to give yourself at least a full year to train for a marathon. You may wish to also consider other goals for the time being – like a half marathon within 9-12 months. These can all contribute to your marathon training journey.

To reiterate, the key to marathon success is to give yourself plenty of training time. The idea is you want to build up that solid running foundation, which allows you to run 20-30km/week over three or four runs. It can help to incorporate shorter running events (5k’s, 10k’s and half marathons) into this period. Now you have the foundation to use as your base to start a 3-5 month marathon training plan.

Check out some of our downloadable, free marathon training plans here.

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Thomas Watson is an ultra-runner, UESCA-certified running coach, and the founder of MarathonHandbook.com. His work has been featured in Runner's World, Livestrong.com, MapMyRun, and many other running publications. He likes running interesting races and playing with his two tiny kids. More at his bio.

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