Marathon Training: Building Base Mileage

Have you ever heard runners talking about  building base mileage up in preparation for training and wondered what that exactly meant? Or have you ever said you’re building your base, but if you were asked, probably wouldn’t be able to explain how?

While I was out on a run last week, I was thinking about the idea of building up a base before getting into a training cycle, since that’s exactly what I’m doing right now. I’m running the Vermont City Marathon on Memorial Day weekend this year, so my training for that race will begin at the end of this month. If you’d asked me a few years ago how to build up a base for a marathon, I would have told you it was all about getting up to a certain number of miles per week before jumping into a plan which would usually start at 20 miles a week (for a conservative plan).

Now, my approach is different. It’s not just the weekly miles you body has to get used to, it’s the stressors of different workouts you will be putting yourself through. Here’s an approach to building base mileage which will get you more than ready for the training to begin.

Marathon Training: Building Base Mileage. Starting off a marathon training program with a good mileage base is more than just the number of miles you run in a week. Try this easy approach to getting yourself ready for marathon training without getting burnt out or injured. | run chat | running tips |

Marathon Training: Building Base Mileage

This is a threefold approach to building your base. You want to accomplish three things in this period of time when you don’t need to follow a set training plan, but need to be in shape to do so soon. You need to be gradually increasing the length of your long run; you need to be incorporating some form of speedwork; and you need to be focused on rest and recovery.

Increasing Your Long Run

Depending on your ability, the length of your upcoming training cycle and how aggressive your training plan will be, your long run to begin a training plan for the marathon could be anywhere from 5 to 12 miles. It helps if you choose the program you’re going to be following as early as you can, so you know exactly where your presumed starting point will be. You can do your long run by mileage or by time – I highly recommend trying the time approach, especially during this base building period.

Running your long run by time can take some pressure off you to be hitting a certain distance each time. You don’t need the mental pressure of hitting an exact mileage just yet – you’ll have plenty of time for pressure during your actual training program!  Realistically, you’re getting your body ready to withstand running for a longer period of time when it comes to marathon training, so this approach can work well for the pre-training phase. Sometimes you have a crappy run and you don’t hit a pace you were expecting, but if you planned on an hour and you ran for an hour, then you’ve stressed your body appropriately and you can feel good about having fulfilled that commitment to yourself.

Don’t obsess too much about this aspect of building your base – the idea is to add a little more time, or a little more mileage, each time you head out for your long run. Worry less about pace and try using this time to check in on posture and what you start doing as you tire physically – this can be a great indication of areas to focus on when it comes to strength training (more on that in a little while).

Incorporating Speedwork

The speedwork day on my training program is always the one I simultaneously dread and looked forward to. I know it’s most likely going to be hard and suck and make me feel like I might die at some point during the workout (hence the dread, just in case you were wondering). The looking forward to it part comes from knowing how freaking accomplished and amazing I will feel having knocked out a hard workout that made me nervous. 

Speedwork, by its nature, is regimented. When you’re running intervals, it’s planned out down to the number of seconds you’re recovering between repeats. You have paces to hit, mileage to keep track of and what time you need to kick it into gear again. (Which, by the way, is why I’m so psyched my new watch can be pre-programmed with intervals workouts so I can take some of the thinking away.)

When it comes to building base mileage, however, speedwork should be way more loosey goosey. Think fartleks, think strides, think about a couple of intervals rather than 6 or 8, thrown into the middle of a run. The goal here is to remind your muscles what it feels like to go fast; to rebuild those fast-twitch fibers so once you get to your first official speed workout of your marathon training plan, you don’t collapse in a wobbly, sobbing mess at the end of it. Or halfway through.

Once a week, take a shorter mileage run and do some form of speed during the run. Fartleks are a great, easy way to transition to a more formal training plan. Pick a spot in the distance and run a little harder until you get there, then go back to your regular pace until you choose the next marker. It’s as simple as that and you’re totally in control. I’ve been doing this, as well as another method, where I just try to negative split a run. If it’s 4 miles, I want each mile to be progressively faster. It’s not officially a speed workout, but it is getting my body ready to run harder as it gets more tired.

Rest and Recovery

Respect your rest. A marathon training plan is no joke. Building your base mileage is not the time to try out doing a running streak on a whim, for example. I aim for three runs a week right now –  a long run, a short run with a little speed, then a recovery run of a very easy, slow pace (which I don’t even check). That’s 4 days off running a week. It’s a good time to get some strength training done, or yoga, or hiking – all the things that will be harder to incorporate once you’re prioritizing your time to running. And take at least one full rest day per week, of no training or strenuous activity. I’m talking Netflix and PJ’s here, people. 

Marathon Training: Building Base Mileage. Starting off a marathon training program with a good mileage base is more than just the number of miles you run in a week. Try this easy approach to getting yourself ready for marathon training without getting burnt out or injured. | run chat | running tips |

When it comes to recovery, think prehab and rehab. Strength training is vital for runners (which is why I’m so excited to start Laura’s Reset for Runners next week, with its emphasis on resistance training). It’s also a great way to address issues before they have a chance to take hold and become a problem, or an injury. I mentioned earlier that your long run is a good time to check in with your body and see what might need focus. Is it your hamstrings that are complaining? Do your shoulders tend to bunch up and forward? Does your lower back ache? Those are your cues for what you can now focus on in your strength training – the prehab section of recovery. If it’s your hamstrings, work on those glutes to make them do more of the work. If it’s your shoulders, emphasize rowing and pulling movements to strengthen your upper back. If it’s your lower back aching, address any pelvic imbalances you may have by working on your hip mobility and strength. You get the idea. This is your prehab, sorting out your weak spots so they don’t become aggravated when your body is under more stress.

For the rehab portion, now is also a great time to become acquainted with your foam roller, your stick, or whatever you use for self-myofascial release. Make it part of your workout to be getting a self-massage of your muscles to keep your fascia knot-free and supple, so your muscles can work to the best of their ability. Rehabilitate those muscles back to feeling like they can withstand the beating you’re planning on putting them through (they can!). Get a good post-run stretch done, so you’re used to the routine of it when you start your training proper.

Finally, don’t forget sleep, hydration and nutrition. These are all key, yet often overlooked, components to training which can greatly impact your performance. Experiment with what makes you feel best in all three of these areas while you’re in this base mileage building phase, so when it comes time for your mileage and intensity to increase every week for at least the next four months of your life (gulp), you already know what works and what doesn’t.

What do you do when you’re building base mileage? Do you go into it with a plan, or not worry about it until you start following a training program? I’d love to hear if any seasoned marathoners have done different things before their marathons – what worked best for you?


  1. Sending this to my sister who consistently seems to get injured training for her marathons. I think she does it during speed work? Love love love the school tykes ๐Ÿ™‚
    Carla recently posted…3 feelings I desire for 2016.My Profile

    • Carly Pizzani says:

      Thanks Carla! ๐Ÿ™‚ I think what I love most about your comments is it’s like solving a whodunnit to figure out what your autocorrect is trying to tell me! ๐Ÿ˜‰ I re-read my post, thinking “School tykes? Did I accidentally upload a picture of my brother and I in school uniforms when we were little?” Then I saw the second picture and ‘ohhhhh! Now I get it!” Please never correct your autocorrects!!! ๐Ÿ™‚

      • haha I love it, I was sitting here contemplating school tykes as well. I am well known for my typos especially when I comment from my phone so I can appreciate this one.
        Nellie recently posted…Workouts On FleekMy Profile

  2. Good luck building your base mileage. In all my marathons I have not really followed a training plan due to my work schedule so I don’t really have any advice. I did make sure I got at least one longish run in per wk. Foam rolling is something that I need to work on more. recently posted…Running My First Ultra MarathonMy Profile

    • Carly Pizzani says:

      You are such a natural runner, Lacey! I seriously don’t know how you run long distance without formal training, but every time you do great!!

  3. Great post! I am running my first marathon on April 3rd – and still wondering what the hell I was thinking signing up for a HARD 26.2! I haven’t started speed work yet. I’m still kind of confused about it, but I now have my very first Garmin (Forerunner 10) that has a run/walk interval setting. I figured I could use that to alert me for speed work. It’s always scary trying something new!

    • Carly Pizzani says:

      Speedwork will help so much! You could try mile repeats to start out, see how they feel. Definitely use your watch to program them, it makes it way easier not to have to think about it and just be told when to start and stop.

  4. I generally try to keep my mileage up around the 50k per week as my base. From there it’s not too much of an ask to bump up to the higher levels needed for a marathon and my body seems to cope well with it. But having said that I’ve dropped my mileage for a month to get a bit of a rest before the year takes off again. I think my body will thank me for it.
    Char recently posted…We Can Do Hard StuffMy Profile

    • Carly Pizzani says:

      Sometimes you just need to have a break! And just like tapering before a race keeps you fresh and ready to run, I oft find if I’ve been running less than usual, when I get back to it I surprise myself.

  5. This is such an informative post, Carly! I’m about to start training for my first 30K marathon and will definitely keep your advice in mind as I go along. ๐Ÿ™‚

  6. This was SO extremely helpful for me! Since I have unofficially decided to tackle NYC again I will be depending on your amazing information and insight to see how I can do things differently hopefully for a better result.
    Nellie recently posted…Workouts On FleekMy Profile

  7. So helpful, thank you Carly! My main issue is that i ‘ll stick to my training plan (that ‘ve spent days putting together so it’ll work around my schedule) for about a week maybe two and then life happens and i start changing days/runs etc. It still works but it can be very distracting since you end up not really knowing what to do when… I mean i know that this is the whole reasoning behind planing but i still need to work on it! I am unofficially training for the Vitality half in London which is in March, its going ok till know but i have to up my game the nest few months which means “Ellen for once just stick to your plan!!!!”
    ellen recently posted…Quit Smoking 101My Profile

  8. I like the balance in your weekly routine. You give yourself rest, while creating time for stretching and other activities that build strength and resilience.
    Thanks for all the great suggestions!
    Melissa recently posted…7-Minute Strength Workout for RunnersMy Profile


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