When Are You Ready to Run a Marathon?

A few weeks ago a runner emailed me and said:

“I started running a few weeks ago and I’m up to 9 miles per week with a 4 mile long run. I’m also working on increasing the run portion (I’m walking every few minutes) of all my runs.

I signed up for the Marine Corps Marathon this fall and am interested in a custom training plan to help me finish strong. My biggest goal is to finish the marathon without any injuries. It’s in 22 weeks – do you think you can help?

My first reaction was shock: new runners with weekly mileage levels in the single digits shouldn’t put themselves into this kind of situation! Unless of course, you find running injuries adorable.

Covering 26.2 miles on foot – or in other words, taking about 33,000 steps – is a physically exhausting, humbling, and potentially dangerous endeavor.

And here at SR, I try to be your coach even if you never hire me – a coach by proxy. I look out for your well-being when it comes to your running goals, which is why Strength Running presents one unified coaching philosophy (instead of 50 writers all contradicting each other that leave you wondering what to actually do with your running!).

So I steered this person away from a mammoth goal like a marathon. See, I don’t push a lot of “rah, rah you can do it if you set your mind to it!” nonsense. Instead of irresponsibly selling this woman a training plan and making a quick buck, I likely saved her from a few overuse injuries and a disappointing first marathon experience.

I’m a straight shooter, so let me tell it to you straight: marathons are hard. While I think almost anyone can do one eventually, it still takes the right preparation. But once you get your marathon training right, you can safely run 26.2 miles – and even run it quite fast!

Why is Running a Marathon So Hard?

An interesting thing happens to our bodies after running for roughly 20 miles: we use up nearly all of our carbohydrate, the body’s preferred fuel source for strenuous exercise. When it’s gone, we have to significantly reduce our effort because we don’t have the rocket fuel to maintain that pace (we have a lot more fat, but fat can’t fuel the intensity level of running a faster pace).Survive the Marathon

Let’s not also forget that the high levels of fatigue and muscle soreness that accompany hours of running lead to a deterioration in running form.

For a fun experiment, cheer marathoners on at mile 25 and notice how their form has gone to hell in a hand basket: leaning from the waist, aggressive heel striking, over-striding, or even limping.

Who would have thought that marathons could be so humbling?!

But the unique challenges of running a marathon lead to an equally unique collection of post-race problems. While you might be familiar with 3-5 days of significant soreness after you finish, that’s just the tip of the iceberg when it comes to marathon recovery.

There’s also a host of other issues going on:

My runners now know why I DEMAND time off after a marathon!

If preparation is your #1 priority for the marathon, then proper recovery needs to be a close second.

How to Know if You’re Ready to Run a Marathon

I have a simple philosophy when it comes to the marathon: if you’re ready to do the training, you’re ready to commit to the marathon.

This boils down to a few criteria:

Time. Likely the most important because it dictates how quickly you can progress in your training. Most runners need 3-4 months of specific marathon preparation. The less you run per week, the more time you need.

Long Run Distance. Since it takes 3-4 months to prepare for a marathon, you can’t start from scratch and expect to be ready in 16-20 weeks. Instead, your long run should already be at about 9-12 miles. If your LR is 4 (like the runner I talked about earlier), you simply don’t have enough time to increase that run safely to where it needs to be.

Weekly Mileage: I recommend you start marathon training at a weekly mileage level of at least 20-25 miles. If you’re just starting to run and the idea of a 20 mile week seems daunting, you’re just not ready yet.

These are the “bare minimum” essentials for knowing when you’re ready to start training – what I call your fitness foundation. In addition, there are a few other “nice to haves:”

Workouts: Complete one faster workout per week after 2-3 weeks of running strides. Start with foundational workouts like steady-state efforts, progressions, and fartleks.

Strength Work: Any good program comes with a healthy dose of runner-specific strength work (which is why all of my training plans include it – which you won’t see on those downloadable plans you can get online). Specific routines – including progressions – are included in Injury Prevention for Runners.

Our companion video is also helpful:

These elements are the building blocks of not just sound marathon training, but training in general.

The Value of Being Process Oriented

Beginner runners will see the most success when they focus on the PROCESS of training – what many coaches call taking the “next logical step.” This approach won’t force you to rush your training or fixate on mileage and long run numbers instead of how you feel. Instead, you’ll incrementally run more, run longer, and run faster in a gradual and systematic way.

But I know it’s not sexy. It’s not the newest fitness class or CrossFit WOD that promises shredded abs or the ability to run an ultramarathon in just a few months for a beginner.

But it works. And as your coach by proxy, I ask more of you. I want you to achieve all of your running goals so I only give you the best running advice possible – including what not to do.

And sometimes, that means giving you a nudge in the right direction… even if that direction is admittedly a little boring (but trust me, sitting on the sidelines with an injury is much more boring!).

Don’t Make Decisions Out of Fear

A few months ago I had a short conversation with a runner who needed a nudge in the right direction – after she received her custom training plan, she asked for a refund because “it makes me nervous.”

I knew it WAS right for her and she was making a decision based on fear. So I told her that being nervous is normal and that I don’t want her using fear as an excuse to use another plan that she considers safe (but ultimately less effective).

She agreed and used her plan. Then a few days ago I received this email from her:

I decided that you’re right – if you do what you’ve always done, you’ll always get what you’ve always got. And I ran a 5k today (4th of July) and finished with a 28:57 time. I haven’t been under 29 minutes since 2008.

I also realized today that I haven’t injured myself since early April. I’m praying the healthy trend continues.

This runner needed the right encouragement – and that encouragement was to focus on the process of sound training, even if it looked different and made her nervous. Now she’s running faster than she has in six years and has a significant healthy streak going!

The same can help you run a successful marathon… once you’re ready to train for one.

If you want to see specific workouts, strategies, and injury prevention tactics that help you be more process-oriented, I’ve created a free email series that you get just for subscribing here.

We’ll learn about marathon training through the prism of injury prevention – helping you stay healthy as you build mileage and the distance of your long run.

Sign up here and I’ll send everything to you.

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  1. Hi! This was a timely read for me… I began running 20 months ago and have done 6 halfs with an eye to my first full on Aug. 9; my long runs were typically in the 10-12 mile range until May when I began to increase, from May through June I increased by 1-2 miles my long run each week and on July 4 did 20 miles. It was hot and some of it was hell – I hit a wall at 15 miles and another one at 17.5 – and I think I need to work on fueling and hydration. But, I didn’t feel bad at all after running that (or the 18, or the 17). I use a combo of run-walk, 8:1 intervals, and I cut that when I need to. My question is, and I am sure you don’t get this from most – what do you consider too slow to be running a marathon? I chose a race with a very generous time limit, but I am really, really slow. I should do more speed work but was focusing on getting my mileage up – should I still go for it? And afterward – what should I do in order to get faster for the next one? I don’t need a ten minute mile, I just need faster than I am. Thanks!

    • You’re a month away and you’ve already run 20 miles, so I say go for it! I think runners over 5.5 – 6 hours put themselves in a risky position for injuries/other problems, so if you’re at that level it’s probably best to focus on short distance races (and that’s a good way to get faster for your next marathon too).

  2. Jason – I purchased your Injury Prevention for Runners program about two weeks ago and think it’s fantastic! I did have one question for you – in the program, a runner is supposed to stop running if he/she feels a sharp or stabbing pain that results in altering the runner’s stride. Right now, I have a tweaky right hamstring. I am able to run, if I run slowly enough – well below my normal easy pace. However, I cannot do any of the speed work (i.e., threshold runs, intervals, or fartleks) that are called for in the program because then I feel a sharp pain and have to adjust my stride. Even though I can run slowly, would it be better rest for a couple of weeks and concentrate solely on the strength training exercises – or should I keep running (even if it’s very slow) and then introduce the speed work when my leg feels better? Thanks for all your coaching advice!

    • Thanks Chris! I’d take 3-4 days of no running but consistency with the strength work and then see how you feel on an easy run after that. A few weeks is just too long – I don’t like being that passive. You can repeat this process until your back to 100%, which should be soon since I don’t think this sounds super serious. Good luck!

  3. Hey Jason, this was also great timing for me as well and has really gotten me thinking. I’ve been an on-again, off-again runner for the last 20 years. I’ve run a few halfs and a large number of 5ks, 10ks and 15ks (Tough Mudder and Boilermaker FTW). My last “off-again” lasted a good 7 months (injured my IT band on a 20 miler that I should not have done, about 5 days after a half-marathon – learned my lesson and never want to be injured again) and I’ve been “on-again” for about 3 months; back into it trying to work on adding mileage. I’m at 20 miles per week and over 10 miles on my long runs. I’ve been at adding 2-3 miles per week (1-2 miles for my long runs), but mostly straight basic running and stretching. I, too, am in the 10ish-minute-mile club and don’t mind the speed, but I would like to get my first Marathon in around late Fall and would like to work in some strength training. Maybe this would take a more personalized approach, but I really do not know where to start as I am a dumbbell “dumbbell” for sure. Any initial ideas?

  4. Hi Jason,
    Since the beginning of the year, I became interested in marathons. Normally I enjoy running at least 3-4 times per week just under 3 miles. I’ve been running like this for at least 4 months now. I’ve known about this half marathon for about some time and change my mind back and forth about whether I think I can actually do it. There are about 4 weeks left till the half marathon. I guess my question is, is 4 weeks enough time for me to increase my running (without injuries) and what tips can you give me to overcome my fear of not finishing?

    • You don’t have enough time…. My very general rule is to have a runner safely build to a 10 mile distance at least two weeks before a HM so that they’ll be able to finish the race. You’re not there yet!

  5. Lawrence says:

    Hi Jason – thanks for another great article. Your coaching plan has really helped and I did my first 10km last week but…now I’m really getting into running and have been reading as many books that I can and have come across Ultramarathons written by people like Scott Jurek. It sort of makes me feel like it wouldn’t be such an acomplishment to complete a “normal” marathon even though I know it would probably take me a year or two so to get to that level!
    Also with you highlighting the damage to the body a marathon takes I do wonder how the Ultra’s survive??

    Really enjoying the site – Thanks.

    • Simon Porteous says:

      I’ve done a couple of ultras and my recent marathon was more taxing because of the higher speed.

  6. Simon Porteous says:

    Another great and timely article, thank you. I finished my first marathon 2 weeks ago. While I was prepared for the physical stress and pain that required a cautious recovery I have been surprised by the psychological toll it took on me. Marathons are hard, especially trail marathons with 4km of soft sand at the 32km mark! I just wasn’t prepared for how hard it was going to be.

    • 4km of soft sand–that’s like my nightmare run. I can barely stand to run in the sugar sand to get down to the hard wet sand on the beach. That’s a cruel course design there.

  7. Alan Hindmarsh says:


    I have just completed the 10 Peak challenge in the lake District in England 73K and 5600 metres of acsent in 23hrs , i know i could probably knock a couple of hours off that next year with some structured traing and advice ( The event is next July) can you advise ?

  8. This showed up in my RSS feed the day after some people asked me to do a half-marathon that’s coming up in November, so this is pretty relevant to me right now. I’ve only been running regularly since last Sept-Oct, but I’ve just now gotten myself up to 20 miles per week, and my longest run so far has been 7 miles, so it sounds like I can manage this if I’m careful about increasing volume and don’t get injured in the meantime. I’m certainly not going to consider a marathon any time this year, but would that be a realistic goal for next year? My immediate goal right now is to get up to at least 10 miles on my long runs and at least 25-30 MPW overall.

  9. Stephanie says:

    Great article! I have been wondering for a while when I’d be ready to tackle a marathon. I’ve been running almost two years with one half marathon under my belt. Right now I’m doing a training plan right now for a 5k this fall, that has me peaking at 32 miles per week with a 9 mile long run, with faster workouts, strides, and strength training several times per week. Sounds like I am a perfect candidate for an Spring ’15 first marathon! I can’t wait!!

    Now I just have to decide… PR Race Plan, Injury Prevention for Runners, or joining Run Your BQ? You have too many awesome-sounding programs Jason. 😉

  10. I’m glad you posted this. When I first started running, the only thing on my mind were marathons, and I’m sure lots of people starting out will find this post very useful. Keep writing!

  11. Thanks for this great article. I’m glad that I found your website, your coaching plan has helped me a lot and I am improving faster than ever before. Thank You!

  12. This is such a great read! I agree running a marathon is no easy endeavor! I even think even with complete training it does not guarantee you can run this race without injury. It’s like a journey with no certainty but as always with practice comes perfection or well, comes with less or no injury for that matter! That’s why we need support and appropriate training and professional advice.

  13. Thank you for this artilce. I really liked that you metioned that new runners have biggest succes then they focus on the procces.


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