Want to be prepared for your marathon? Run More Miles

Whether you want to run a marathon in the future or are ready to embark on your first marathon training cycle you’re probably wondering what kind of mileage commitment to expect. As a seasoned runner you may be working toward a personal record and wondering if increasing your mileage will help you. Here you’ll find out what kind of weekly mileage it takes in training to run a marathon well.

The old adage of “you get out what you put in” rings true when it comes to marathon training. I finished my first one way back in 2005, but it wasn’t pretty. Let’s just say I was crossing my fingers and hoping my “less is more” strategy would work. It didn’t. Had I run more miles during my training and built that mileage up to an optimal peak number, I know I would’ve had a really great experience.

So, how many miles per week should I run in marathon training? The optimal mileage to run a marathon well will be between 40 – 70 miles depending on your goals. Building up your running mileage in marathon training is going to prepare you for your marathon and help you in the areas you’re looking to improve. For example, do you want to:

  1. Run faster?
  2. Avoid hitting the dreaded “wall” so many experience between miles 18-22 of their marathon?
  3. Build mental toughness?
  4. Avoid injury at your marathon?

Your best bet in each of these scenarios is to RUN.MORE.MILES.

You will definitely find shortcuts when it comes to marathon training. I recommend you quickly run from those options. I’m not saying you can’t run a marathon by doing the “minimum.” But if you truly want to improve and set personal records, it’s time to up the mileage.

Higher mileage marathon training will get you to the finish line happy.

The “Magic” Mileage Number for Marathon Training

Depending on your experience level with endurance running, the exact amount of miles you’ll need to run each week to accomplish your goal will be different. No matter what time you’re seeking, my guess is that you want to have a good experience and my hope is that you’ll want to do it again. Trying to run a marathon on only 3 days per week with peak mileage reaching only 25 miles per week (that was my 25-year-old self) can be done, but it’s far from ideal.

Follow the guidelines below depending on your level.

Beginner Marathon Training Mileage

You are about to embark on your first marathon or maybe only have a couple under your belt. You’ve been running consistently up to 25 miles per week and are ready to train for a marathon. You have a goal time above 4 hours 25 minutes.

I recommend:

  • Going into marathon training with a base of 20-25 miles per week.
  • An 18-week training cycle.
  • One long run per week increasing up to 20 miles.
  • Hitting peak mileage on the 15th week with at least 40 miles.

Intermediate Marathon Training Mileage

You have run at least one marathon before and are comfortable training for other shorter endurance races. You do well sticking to a plan and are ready to commit to training more each week in order to work toward a personal record. Your goal time is close to or under 4 hours.

I recommend:

  • Going into marathon training with a base of at least 30 miles per week.
  • A 17-week training cycle or longer.
  • One long run per week increasing up to 20/21 miles; one mid-long run per week up to 9 miles.
  • Hitting peak mileage on the 14th week with at least 50 miles.

Advanced Marathon Training Mileage

You are an advanced marathon runner if you’ve run several marathons and are ready to take it to the next level. Maybe you are looking to qualify for Boston, have hit a plateau in your marathon accomplishments, or are just looking to find out what’s going to give you the edge you need. You run consistently most of the year even when you aren’t training for marathons. You have a goal time under 3:40 minutes.

(I’m not talking about elite runners here. Running 100-mile weeks for them is not uncommon!)

I recommend:

  • Going into marathon training with a base of at least 35 miles per week
  • A 17-week training cycle or longer.
  • One long run per week increasing up to 21 miles; one mid-long run per week up to 10-11 miles.
  • Hitting peak mileage on the 14th week with at least 60 miles.

For some advanced runners, getting marathon training mileage closer to 65-70 miles will allow for even greater gains. As a working mom of three kids, I personally have a very hard time fitting that much into my weekly schedule. I know you probably will, too. But it certainly can be done – and if you’ve already gotten to 60 miles per week and aren’t seeing the improvements you want…getting closer to that 70-mile mark will probably help a lot.

As far as an “exact” magic number, in my head, it’s always 60. I worked really hard to get to that last year, but it was tough. If you’re not there yet, that’s totally fine! Do your very best and give yourself some grace. Just know that as you look to progress in your times for the marathon, adding mileage is going to most likely be something you’ll need to do.

Can I run fewer miles, but run them faster?

So many people hope that if they just run fewer miles, but run them faster, they’ll be able to still hit their target pace in a marathon. I hate to break it to you, but it just doesn’t work that way. Trust me, I’ve tried.

Low marathon training mileage will leave you bonking at mile 20.

Let me tell you a little story.


When I trained for my first marathon back in 2005, I definitely went in with substandard mindset. Even though I joined a marathon training group for my Saturday long runs (smart choice), I basically put in the minimum possible miles the rest of the week (poor choice). I definitely thought to myself, “How can I accomplish this 26.2 goal by running as few miles per week as possible?” Not great, right? Yes, I was a busy, brand new teacher so it wasn’t as if I was against working hard, but I honestly probably wasn’t ready to run a marathon and I’m not sure I was doing it for the right reasons (or if I even knew what those were.)

Yes, I finished – which is a huge accomplishment in itself – but I hit the wall hard at mile 19. There was a lot of walking. It was a pretty miserable experience those last 7 miles where I wondered if I would make it. When I ran the Portland Marathon in 2007, I had a similar experience. After that, I wouldn’t run another marathon for 10 years.

Had I run more miles and adhered to my plan, maybe I could’ve progressed through the years instead of just assuming I wasn’t cut out for endurance running.

In 2017, I decided to give it another go. I made a promise to myself that I would find a proper marathon training plan and stick to it. One that would allow me to run an entire marathon without walking or injury. And that’s what I did. Upping those miles helped me get a one hour PR!

The number of miles per week a person runs directly correlates with how well and how fast a person can run a marathon. This article from the Guardian has a couple of great graphs to prove it. They state, “Mileage is the most basic measure of marathon preparedness.”

It’s not the only piece, but it’s a huge factor. You need both quality AND quantity to excel in a marathon. Running fewer miles at a faster pace isn’t going to help your cause in an endurance event like the marathon.

More Miles Is Usually Better for Marathon Training

By now you may be thinking, but why is running more miles the golden ticket?

Here’s a little rundown of why it works:

  1. Build Cumulative Fatigue – I have an entire article devoted to this topic here. Basically, you can’t learn to run on tired legs if you are only running 3-4 days per week and/or too low of mileage. Every time you run, you are recovered. Well guess what? Your legs feel anything but recovered by the time you get to 16 miles or so. Going in unprepared mileage-wise leaves you at high risk for your legs seizing up.
  2. Build Your Aerobic Engine – As a runner, you know what it feels like to take several weeks off and feel completely out of breath when you try to get back into it. You also know what it feels like when week after week you are putting in the work and it becomes easier to run farther, longer, and faster. That’s your aerobic system at work. As you run more often, it becomes easier for your body to move oxygen around your body to create energy mile after mile. It takes time and a long build-up of miles to sustain the aerobic capacity necessary to achieve your marathon goal pace. This means A LOT of your miles will need to be run slowly.
  3. Mental Preparation – If you’re already going into marathon training wondering how you can accomplish this by doing less, you’re already behind in the mental game. Getting through a marathon is just as much about physical preparation as it is mental. It takes grit and perseverance to get through 26.2 miles when you feel like you can’t go one more step. This comes from the mentality that you’ll do whatever it takes. Those grueling high-mileage weeks are just as much about building mental toughness as you argue with that little voice in the back of your head trying to convince you that you can’t do it.

In order to sustain a particular pace without bonking (where you instead get slower and slower each mile) and get faster you most likely need to prepare better with higher mileage weeks.

Increasing weekly marathon training mileage will give you a good marathon experience.

Safely Increase Weekly Mileage to Hit Your Target

Even though you’ll need to run more miles to hit your marathon goal time, there is a safe (and unsafe) way to go about it.

Proper Mileage Increase

Above I mentioned the proper base a runner should have as they head into marathon training. This is because, for example, if an intermediate runner is going to top out at 50 miles in one week, they need to slowly increase mileage to get there. Going into marathon training with only a 10-mile per week will not safely get a runner to 50 miles by week 13.

The golden rule of mileage increase is to never add more than 20 percent to your previous week’s mileage. Beyond that, you also need to add in cutback weeks or a slighter increase. So weeks 1-5 might look something like this: 32, 35, 38, 36, 39.

Trying to go from 30 miles in a week to 40 the next is just going to get you hurt. Think plantar fasciitis, Achilles tendonitis, and shin splints. Ouch.

Proper Pacing

Another big factor to consider when increasing your miles is the pace you’re completing it at. In my article “Train Slower to Run a Faster Marathon” I talk about how running slower will allow runners to be able to run more miles safely to hit the higher-mileage weeks they’re after. Trying to incorporate too much speedwork too soon or junk miles (too many mid-paced miles that still place a high demand on your body but don’t help increase speed which I discuss here) is another surefire way to injure yourself.

Running 75-80% of your miles at an easy or recovery pace will ensure that you can hit your target mileage week after week without injury. In turn, you’ll be strong and healthy on marathon race ready to conquer your goal.

Tips for Reaching the Miles You Need in Marathon Training

  1. Find a trusted plan that safely builds mileage with the target mileage you need at your level.
  2. Stick to the plan. Unforeseen circumstances happen but keep these to a minimum and rearrange your schedule as needed to make it work.
  3. Have a “no excuses” attitude.
  4. Do “two-a-days.” This can be tough, but sometimes necessary. It’s also a great way to build that mental toughness. You may only have 45 minutes before work to run,  but 8 miles is on your schedule. Maybe that means you run 5 before work and 3 after. You don’t want to do this all the time, but it’s far better than skipping those extra 3 miles that you need.
  5. Mix up your runs. Doing everything exactly the same makes it much harder to stay motivated. Finding new places to run is a great way to make a long run something to look forward to.

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Marathon Running Tips & Tricks

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