100 Mile Intrigue: Embracing the Unknown

There’s something mythical and mysterious about the 100-mile distance. It is the most intimidating, intriguing, and respected distance commonly raced in trail running. I’ve felt this way about 100 miles since long before I ran my first one – The Susitna 100 in 2006. Before I even knew that an entire sport of ultrarunning existed, I knew about a few of the well-known 100 mile races: Western States, Leadville, Hardrock, and Wasatch. I was both horrified and strangely drawn to the idea that 100-mile running races existed. I never thought I would actually run 100 miles, but I always had an inexplicable curiosity about running that far. It was as though I was curious to run a 100-mile race because I wouldn’t quite believe they existed until I did.

Several years and eight 100-mile finishes later, I no longer doubt whether these races really exist and if people really do run them. There is, however, still something magical and intensely appealing to me about the distance. I think this appeal comes from several places, but mostly from how challenging, unpredictable, and unknown the experience of running 100 miles on trails in the mountains is.

Despite the rapid growth in the sport of trail running, the 100-mile distance is still only attempted by a small minority of trail runners. If you take it a step further and compare it to the marathon or other popular road racing distances, the amount of people running 100-mile races is essentially non-existent. Someone with a lot more patience than I could probably look this up, but my guess would be that more people complete a marathon worldwide in a month than have ever completed a 100-mile race.

It is this lack of precedent combined with the immense challenge that makes 100-mile races so mythical and appealing. So few people have actually attempted to run 100 miles that there really is no proven right way to do it. (I’d like to use the statement that the book hasn’t yet been written on this subject, but one only needs to look as far as the editor of this website to find an actual book on this subject, so this kind of shoots the metaphor dead.)

There are many theories on how to best prepare for and race 100 miles, but you find very little consistency within these theories. Every successful 100-mile runner has found an approach that works for them, but no one’s approach seems to work for everyone. In a recent column on this website, Ian Torrence talks about the necessity of a structured training program which includes a balance of endurance runs, stamina workouts, and speed training. I have only met Ian briefly in passing, but with a resume of over 150 ultramarathon finishes in a nearly 20-year career, he is someone I take very seriously when he writes about how to prepare for an ultramarathon. The problem, though, is that when I take into account my experiences of racing 100 miles, I have found no personal benefit of a structured training program. I am not alone in this area.

The three fastest runners ever to run The Western States 100 – Tony, Kilian, and myself – have something in common in our approach to training that is hard to ignore: we each simply go out and run in the mountains with essentially no structure. The runner who has won more 100-mile races than anyone in the world, Karl Meltzer: the same thing. Unless of course you count shoveling snow and sledding as stamina workouts or speed training. Ian, however, also isn’t alone in his belief in a structured training program being an “essential element of successful ultramarathon training.” As evidenced in the responses to Ian’s column, many 100-mile runners seem to benefit from a more traditional, structured training program that includes regular stamina and speed work. What works for one often seems to have no benefit for another, but it is the success of these diverse approaches that makes the 100-mile distance so elusive and intriguing.

The question then that begs to be asked is who is right? How can so many people disagree on something so intrinsic to the sport as to whether structured training is necessary to be fully prepared to race 100 miles? The answer, of course, is that no one is entirely right, and no one is entirely wrong. And herein lies the appeal of the 100-mile distance: none of us really know what we’re doing when it comes to 100 miles, and the aspiring 100 mile runner who has yet to race her first step, has a better chance of figuring out what works best for her than anyone else does. I have people ask me all the time what advice I would give them for preparing for their first 100 miler. I usually give them a few basic logistical tips, and then tell them that all they can really do is go out and run until they find out what works for them. And, lastly, I tell them to be skeptical of anyone who tells them that they know definitively what type of preparation is going to work best for them.

Eventually, the practice of running 100 miles may become so commonly attempted that a definitive best method will evolve and come to the surface, but I think this will be a sad day for the sport. So much of the intimidation, intrigue, and appeal of running 100 miles comes from the reality that none of us really know what we’re doing.

Call for Comments (from Bryon)

  • What intrigues you about the 100-mile distance?
  • Do you think there’s a best approach to training for a 100-mile race? If so, what is it?

There are 81 comments

  1. Jason

    I've not yet run a hundred-miler (next year!), so my opinion may be irrelevant. During a "break" from just running, I did Ironman and lots of other triathlons, following a very structured training program (no coach, however). What pulled me back into running (besides moving back to the mtns and just being sick of tri culture) was the freedom to just go out and run – as far and as fast (or slow) as I wanted. It's what has kept me going the last few years as I've been climbing the proverbial ultra-ladder.

    With 7 or 8 ultras under my belt (50ks and 50 milers), I've found that a "flexibly structured" training schedule works really well, for me. I have a good sense of how much weekly volume I can handle, as well as how gradually I can increase that volume w/o injury. I know that I'll have to increase the volume as I get closer to the 100 mile distance. Knowing that I need to get in roughly x amount of miles, elevation, etc, as well as those ever-important long-runs, I construct a rough schedule of what I *should* do rather than what I *must* do. If I miss, that's ok, and I shouldn't try to "make-up" for it. If I'm feeling especially strong on a run and stretch it out by a few miles, great!

    I don't know if the same strategy (albeit w/ more volume) will work as I prepare for my first try at 100 miles, but I appreciate Geoff's affirmation that it'll probably be alright! Thanks for a great piece. If nothing else, it's a reminder that at the end of the day, going for long runs through the mountains shouldn't follow a time of anxiety about a micromanaged schedule that compromises the freedom we enjoy by being out there in the first-place.

    But then again, I haven't done 100 miles, so don't listen to me!

  2. Max

    Here's a few QUOTES by Geoff that prove his point:

    I don't plan any kind of workouts.

    I'll be running, but not with any kind of focus on training until next month.

    Training with a specific focus and purpose of trying to be as fast as possible on a given day at some point in the future feels so shallow and silly to me when compared to simply going out and doing the run that feels the most logical, enjoyable, and appealing on each given day.

  3. Jeff

    I would echo some of the comments made by others. The content is good, of course, but the writing is excellent. It's refreshing to read well-written and thoughtful articles about an activity I love. I enjoy reading Tony's articles in RT for the same reason.

  4. Jason Thompson

    Hi Geoff:

    Thanks for the thought-provoking article. It strikes me that, beyond structure, perhaps a more fundamental (albeit less quantifiable) factor in terms of the optimal approach to hundred milers is sheer passion. I’ve noticed how a common characteristic of the most successful ultra marathoners — yourself included — really does seem to be a genuinely joyful relationship to the act of long running adventures in the mountains (and by “successful” I don’t just mean the front-of-the-pack.) I’m reminded of Matt Fitzgerald’s argument (in his book “Run: the Mind-Body Method of Running by Feel”) that running performance is highly contingent on the extent to which the activity still feels fun, and especially of his analysis of the relatively early decline of one elite marathoner, Brian Sell, when despite massive weekly mileage and serious grit he let the fun factor fizzle out and stopped seeing gains. I’ve heard Killian describe his motivation as really based on seeing the mountains as a type of playground, and I believe both you and Anton have expressed a similar attitude. By any pragmatic measure, a hard mountain hundred miler is such an absurd proposition, perhaps there’s some sort of competitive edge in not so much transcending that sense of absurdity but actually embracing it; on some level relishing even the exhaustion and discomfort as integral to the self-affirming freedom of the trail. As one runner commented in a TV newscast I recently watched about Hardrock: “it doesn’t have to be fun to be fun.”

    –Jason Thompson

    San Francisco, CA

    1. Geoff


      i couldn't agree with you more. i think sheer passion for running is probably the one thing that virtually everyone who does hundred milers successfully has in common.

  5. Sebastian

    I started running in 2006 (at the age of 37) and attempted my first 100 miler in 2009 and DNF'd due to severe ITBS. I gave it another chance in 2010 and got a personal coach four months before the race who made a training plan for me, but ITBS made me DNF once again. I then had a year to prepare for the race in 2011 and with structured training I managed to do the full 100 mile. The dream finally came true.

    For me structured training is the key to enjoy running and to get the best out of the time a spend training. I don't want to "waste" an hour or two on "just" running, I want to know the purpose of every run as I treat them as a part of a puzzle. I love running and don't find that the training plan takes the joy out of it.

    Thanks for a great post, it really made me think.

  6. James Adams

    Great article Geoff and I totally agree that there is no "correct" way to run such distances. Running long distance is so fundamental to human nature like eating or sex that millions of different bodies have millions of different ways of going about it and it is a case of everyone finding their own way. It is unlike a more mechanical sport such as cycling or golf where training and technique are more relevant.


    Take a look at this blog post from a British runner. The top 100 mile runners even pace differently and the world record times have been done with massive positive splits, something that is perhaps inevitable at this distance or maybe not.

    Anyway, if 100 mile running ever gets figured out like triathlon then we need to find another sport. How about mountain pogo?

  7. Ian Sharman

    There's undoubtedly a steep learning curve with ultras and with 100 milers in particular. That's where I think a coach can most help – by talking through all the variables and lessons that need to be considered to run 100 miles. A training plan is part of it, but the advice I received (admittedly not from a formal coach) in the build-up to my first 100 miler was invaluable.

    Plus, as with any training for any type of sport, having an objective third party to help you assess whether you're under or over-doing it, or how best to come back from an injury (we all want to come back too soon!) can make a world of difference to the consistency achieved over time. And I think that's the single most important factor affecting improvement.

  8. matt g

    Surely this applies to all distances and sporting disciplines. There are no definitive training schedules and all athletes vary their programmes widely from 100 metres to 6 day races. I'm sure it would not be difficult to put together a 'get you round' schedule for a 100 miler similar to those that the masses use to get them round their first 26.2.

  9. Noe Castanon

    Good point of view about 100M. In my perspective, every race requiere diferent kind of training. If someone from sea level is running Leadville TRT or Hardrock, necessary must to look for trails with high elevation. HURT the same thing, technical trails. There are very few talented ultrarunners whom can change their running schedule when they want it, the rest of the mortals, no! Thanks for the article.

  10. Ian Stewart

    For me the main reason was to see to see how far I could go without hurting myself too much and a friend called Andy who ran 66 ultras consecutively allowed me to run with him. But now running ultras and especially the magical 100 mile is to visit other places, and enjoy!

  11. Ultrawolf

    Hello from Austria,

    Great piece of writing Geoff, as always !

    In my opinion the more years one is already running, hence the better he knows his body, the less structure he will need in training. A runner with little experience will need a plan how to increase his long run, do hills, etc., otherwise he´ll likely be in top shape in February but burned out later in June when he got THE race.

    There´s no need for someone like you, Geoff to put that down on paper, you simply know when it´s time and what to do to get in shape for Western or Hardrock.

    What I would like to know, do you actually have a diary to keep track of your trainings ? Do you have any clue how many vertical meters/feet you´re doing in a heavy week or is this of no interest for you ? I´m always amazed to see how much Tony´s doing :-)

    How long´s usually your longest run prior to a 100 miler ?

    Best wishes


  12. Ben Nephew

    With small sample sizes you are going to have a great deal of variation, and that is what we have with 100 mile world record attempts. Steve Jones almost broke the marathon WR at Chicago in the 80's with 61 minute first half. That would be like going out in 59 today and running a 2:04. Good luck with that, and let me know the next time the marathon WR is set with massive positive splits. As ultras become more common and competitive, even splits will become more common. It is entirely possible that postive splits are somewhat inevitable for some due to inflammation or mental fatigue.

    Maybe you can't call the massive splits of Woodward wrong because he set a WR, the strategy was effective in obtaining the goal, but do people really enjoy running massive positive splits? The really interesting data would be to see a large group of runners try running both even and positive splits at several races.

  13. Anji Nussbaumer

    I don't think there is a right way to train for 100s other than the old addadge of "Time on Feet" I raced my first 100 two weeks ago and have only been running Ultras for a year and a half. My longest week prior to that race was 50 total miles. I threw in a lot of high intensity strength workouts and tempo runs during the week. I kept it pretty unstructured other than getting the mileage in. My body does not like high mileage and I raced well with a 20:58:19 finish. I have seen great racers get taken out by that distance regardless of training. It is truly and unknown element and that I find very challenging and exciting.

  14. Myles Smythe

    My training is low, similar to Nate. For the past six months my training has significantly declined. I started with a solid base and ended with one 100 mile finish. Life got in the way, but also my realization that my cardio and leg strength were stronger than my gut. So even if I was training at high levels, I'm not able to perform at my peak level over ultra distances. I have been training with 7-15 mile weeks. But still pace friends or run 50K plus races at least once a month, which I count as my long runs. I crosstrain by rock climbing twice a week (great for foot strength, IMO), run any set of stairs I encounter while a pedestrian and stand at my computer at home for 1-2 hours each day. It seems to be working, I'm maintaining my base and my legs/cardio feel fantastic while I race…..but not my gut. I'll maintain this training or lack there of, for WS100 this June. I feel confident that it will work for me.

  15. Adam St.Pierre

    First, I'll admit my bias, I'm a coach working with athletes competing in a variety of events, including ultra winners and first timers. I fully agree that each athlete must find their own way to success. A coach can be an objective 3rd party advisor for any athlete. A coach should not put you on a 1 size fits all training plan. A coach should not "force" you into a cookie cutter training plan, rather communicate frequently to help you determine what works for you and help you dial in your ultra running formula.

    Geoff brings up some examples of successful athletes who “simply go out and run in the mountains with essentially no structure.” No one will deny that the athletes you speak of are successful, but they have other commonalities. For instance, they all run/exercise a lot! I would argue that part of their success is not their training method, but their volume. If everyone had time to exercise 20-30 hours each week, we'd have a lot more "elite" ultra runners. For people who don't have 20-30 hours per week to exercise, they have to train! Training is exercising with a purpose. If you don't have 20+ hours per week to train and you want to compete in ultras, you need structure. Competing is different than finishing. It's possible to be successful with unstructured training, it all depends on your definition of success. For some, finishing is success, others hope to win or finish in a certain time. I would argue that the unstructured trainers Geoff brings up would be better if they did some structured training. Of course, it's hard to think about improving when you win, but if you don't win and set a course record every single time out, then you have room to improve.

    Sorry for the rambling… happy running!

  16. zeke

    Lots of wisdom in these comments. My opinion is that "just running" on Terrain as close to the Terrain you'll race at is the best program, not necessarily because its best practice, although it may be, but because its the best way to just enjoy your training. I come from a very structured running backgrround (running at the ncaa level at CU) and that type of training is just not as fun as getting lost on a trail for hours.

  17. Bill

    Thank you Geoff for the intriguing article.

    It makes sense to me that unstructured training works nicely for long endurance races with many uncontrolled variables but it would be great to have you elaborate on what you mean by "we each simply go out and run in the mountains with essentially no structure." What are some principles that you use to guide your decisions on when and how far to run? Do you decide every morning what you are going to do that day based on the current state of your mind and body? What guidelines do you use for recovery or for when to push your limits by running on tired legs?

    Looking forward to seeing more articles from you!

    Best Regards,


    1. Geoff

      bill, personally I rarely decide what type of run i'm going to do more than a day in advance. sometimes i know that i want to get in a long run and i'll plan it a few days out so that i know i have a day when i'll have enough time to do it. other than that though it's usually just more of a general pattern. i might have a time when i know i really need to get more strength built in so i'll do a lot of vertical most everyday. other times i know i need more endurance so i'll focus more on trying to get in several days of high mileage. that's about it though.

  18. Bill

    Is the point here that we should throw Geoff out of the data set because he is so genetically gifted that his training methods are irrelevant? Another equally valid hypothesis is that he is genetically close to the mean but is a racing results outlier due to his training methods. If that is the case then the rest of us may have some chance to improve our results by learning from him. Anyway, I vote we keep him in the data set and learn from his training methods :-).

  19. AJ

    I don't think there is any one right way to train for a 100. You have to make the most of the environment around you and you have to make the most of your abilities and your mental make up. For example, I don't live near trails with vertical that I can hit every day. So I have to find fitness gains using speed work instead of vertical work. And, quite frankly, I enjoy the competitive, watch-oriented nature of road running.

    I think the factors that ultimately determine success lie outside of training: natural ability (V02 max), experience, nutrition and hydration, a plan to "run within yourself", etc…

  20. James

    I think this is probably true. In addition, I wonder if Geoff and others aren't mindful on their runs and get the threshold and similar workouts by pushing hills (up or down). The beauty of trail running is you have the opportunity to run "easy and long", threshold (pushing pace), turnover (pushing downhill), etc.

    I use a trainer and as a MOP runner (multiple 100 milers), I am able to train 50-60 miles a week and continue to see improvement. Quality workouts can make up for miles/time.

  21. TrailClydesdale

    I think the mental part is so important, and everyone's mind works differently. The workings of the human mind are such a mystery – there will never be a definitive way to train – especially for this distance.

  22. Phillip Gary Smith

    I'm glad my idea of structure, which is basically not one, fits someone of your caliber: go out and enjoy the trails while penciling in days and nights where the timing gods come together to allow the time to be out a long or even longer time. That's more difficult in the world of earning a living with the years of recent unpleasantness, but what is, is. There is nothing better in trail running than training by one's self, at night, with a variety of hills, switchbacks, mountains and other amusements to entertain. Funny; when those things are happening all sorts of creative things go on in the mind, and things that matter in the career-world don't seem to matter too much, particularly after tripping over a hidden root, landing butt-down with a clear view of a big moon above. That'll clear one's head. So, structure really is the art of doing it on the trails. Structure is freedom on the trail; I'll take all of that rigidity I can.

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