The Long Run
As I read and listen to the information available to endurance athletes, it’s clear to me that most workouts are seen as coming from one of three bins, the easy bin, the hard, bin, and the long bin. That is, easy runs, hard interval or tempo runs, and the long run. Sometimes these are combined where, for example, a tempo run is performed inside of a long run but these seem to be the basic ingredients. Today I want to talk about the long run.
The long run is a staple in the ultra-marathon training world. But what is it? Is it a run longer than 15 miles? Longer than 2.5 hrs? Your longest run of the week regardless of distance or time? My answer: it’s whatever run you call your long run - because a label is nothing more than a label. More important is what we’re trying to achieve.
The desired outcome of the long run is usually that the run stresses the body's abilities to persist so that it will adapt, making it a little easier to do that run again in the future. So, it’s not really important that the run is ‘long’, whatever that means, but that the run results in improved endurance or stamina. Remember that I define running endurance simply as how far or long you can run without rest while I define stamina as your ability to sustain a pace or effort level over time, which is a function of both endurance and economy.
Let’s examine how two very different sets of runs can achieve some of the same results.
If you’re fully nourished and rested, it may take you 20 miles to become glycogen depleted and it’s only as you approach this state and push beyond that some adaptations may be stimulated. However, if you complete either the same run or a fatiguing high-intensity interval workout Monday evening, don’t eat any carbohydrates afterward, and then go for an easy run the following morning - starting in the glycogen depleted state - it’s likely that you’ll activate some of those same responses in the first few miles of the run.
Let’s have another example, if you lift heavy weights or run hard downhills that make your quads sore for several weeks, but eat a protein restricted diet, you may lose muscle mass while getting sufficient protein may result in muscle maintenance or even gain despite the workouts being identical in the two conditions.
And a third example: If you have trained your mind and developed a strong sense of gratitude, happiness, calmness and all things positive, then the hormonal state in which your body functions will be measurably different than the one in which your outlook, moods, and thought patterns are predominantly negative. Sleep can have similar effects on your neurochemistry, hormone levels, and the like. Will the stress-response pattern to the identical workouts be different? How could they not be?!
The key point is that it’s the physiological environment of the workout that dictates both the stresses actually experienced by the body and the resulting adaptations regardless of the numbers of repeats, time splits, or even duration of your workout.
After a hard day at work, after poor sleep and not eating well all day, a run that would normally be quite doable may feel like a slog. It’s quite likely that some of the stimuli you wouldn’t normally get until the last part of a long run are actually stimulated much earlier in the run after such a challenging day.
That’s not to say that a 4-hour run can be the same stress as a 40-minute run, or vice versa, just by manipulating how you eat, think, and sleep. I’m simply calling your attention to an advanced and current way of thinking about your training. That the details of the workout may matter less than the state your body is in when you perform that workout.
Good, that’s out of the way. Now we can get back to the long run. What are you trying to accomplish with your long run today? When you're running long, your purpose usually has something to do with developing endurance or stamina, practicing hydration and nutrition, testing gear, or often a combination of these. How can you construct the parameters of the run to meet the purpose?
If it’s trialing gear, then you obviously have to use the gear and you should also have a plan of how you’re going to test it, then journal about how it went - the good, the bad, and what to try for improvements next time. And, hopefully you referred back to previous gear tests to be sure you incorporated on this run what you recommended for yourself on the previous gear testing run.
If it’s testing hydration and nutrition, you should again have a detailed plan, informed by prior test runs. After the run, you’ll record how things went and make recommendations to your future self. Try to change just one thing, two at most, when testing hydration or nutrition or it will be difficult to accurately attribute the outcomes to which thing you changed.
If it’s developing endurance (your ability to continue moving for a distance or time) or stamina (your ability to sustain a pace for the duration of a distance or time), then you have distance and/or time as a central factor in planning the run. Determining that distance or time ought to be a value that is logically and rationally derived from prior runs of similar duration. If you’re training for a race that will take you 8 hours, for example, there’s no need to run for 8 hrs in training. Doing so will be self defeating in most cases as it's beyond the plateau point for stimulating adaptations - more on that in a moment. But let’s imagine that your longest training runs have been 2.5 hrs in the recent 12 weeks or so. Well, then 2.5-3.0 hours might be an excellent choice. And this time, you’re going to try to run those moderate grades that you intermittently walked and ran three weeks ago. Or, you may try to maintain a slightly faster pace. Or you may try to maintain the same effort level as in the past, knowing that doing so will help to make that pace feel easier. Of course, there are limits to all of these approaches. You can’t, for example, expect that running the same route at an easy-to-moderate effort will continue making you faster overall indefinitely. The key point is that you're defining the duration of the run based on recent, similar runs. My general rule for most people is that increments should be no more than 30 minutes after having been at one duration for at least 4 weeks.
Can a run be too short to be meaningful? If you’re an untrained individual, probably not. Even 10 minutes is a notable stress for sedentary individuals. If you’re capable of running continuously for more than an hour then 30 minutes is the minimum duration I - and the science - would recommend for any run of steady, easy intensity aimed at developing or maintaining endurance. This is because it takes about that long for all the metabolic, structural, and organ-level machinery to be pushed sufficiently to nudge the stress response for development, or at least maintenance.
Can your run be too long. Absolutely! At what point do you reach diminishing returns where each additional 10 minutes or each additional mile/kilometer no longer provides the same additional stimulus for adaptations as the previous block of time/distance? We can conceptualize the benefits of any run as having diminishing returns after about an hour. Mathematically it’s useful to think of the benefits following a rate constant of 1 hr.
This is a very generalized guide. Prior fatigue, poor sleep, hard work day, etc. will all shift this curve to the left such that you’re getting all the benefit you can on that day (which will be less) in a shorter run, and you're risking overdoing it by going longer. Overdoing it means longer recovery and higher risk of injury with less overall gain.
The general consensus is that you get most of the benefit of a run in the first hour, less but still enough to justify a second hour, and less still in the third hour. Beyond three hours, the benefits of continuing are small while the risks of breaking down too much increases substantially, risking over-fatigue that you can’t recovery from within 24-48 hours, which is what we want.
Not all runs are the same. If you're in a hilly area, you should separate hiking as a different sort of stress, outside the 2.5-3.0 hrs of accumulated running. Appreciate, also, that terrain - very technical, lots of vertical gain and loss, smooth surfaces, altitude, heat - will all factor into the stress of the workout. Equally important is your current psycho-physiologic state. Are you stressed? Did you sleep well? Are you fighting an illness? Have you eaten properly? Did you have a very tiring interval workout two days ago from which you haven’t fully recovered? Did you just read a Tweet from someone explaining you are no smarter than a sea slug? All these things are the context within which your body is functioning and they all influence the manifestation of stresses during the run that determine the amount of recovery required and that trigger the relevant adaptive processes. Basically, you’ve turned on all the pathways, pushed all the stimulus buttons, stressed all the systems, and engaged all the cells, tissues, and organs to a degree that running beyond that duration gives you more negative breakdown than added positive stress and you’re only going to prolong needed recovery time without reaping much benefit for additional adaptation. Here, we’re defining recovery as the restitution of capabilities to baseline and adaptation as the positive changes that raise you to a higher baseline of capabilities.
Don’t expect much from any single run or any group of runs. How many hours do you run in the 3, 6, and 12 months before a goal event? Over timeframes as large as those, a few long runs are not going to make a massive difference. There is nothing physiologically magical about the long run. All of your similarly paced running counts equally, whether it’s a 90 min run or a 3 hr run. On a 10 hr weekly running budget, you’re better off running 1-2 hrs per day for 6 days than running an hour a day 4 times and then grinding out a 5 hr run on the weekend. If you body is used to running just one hour per day, hitting it with a five hour run is just poking the bears of injury and fatigue.
To summarize, runs longer than 30 minutes will be useful for small improvements in endurance or stamina for some on the lower end of fitness and generally be sufficient for maintenance for most moderately trained runners. Increasing duration of easy-to-moderate runs will provide incrementally greater stimulus for development of endurance or stamina depending on your state of fitness and all of those other psycho-physiologic factors. The efficacy of extending duration of a run reaches a point of diminishing returns by about 2.5-3.0 hrs of running.
Does that mean running longer than three hours isn’t useful? Not at all. Let’s revisit the purpose of the workout. The nutritional strategy that works for you in the first hours of an easy-to-moderate intensity run may be progressively less palatable as you go past glycogen depletion and perhaps become a little dehydrated. Small errors in fluid intake are easily masked by the ability to sustain performance until there’s a 2-3% loss of body mass in water but then become increasingly evident as the hours accumulate. The hydration pack that feels so good for a few hours may begin to chafe after it’s bounced and rubbed the same spot for another 3,000 strides. Dipping into fatigue and extra time on feet can also provide the context and opportunities for you to practice your mental skills. So, runs longer than three hours can be useful for all of these reasons. Use them sparingly and deliberately to test, practice, and hone all of these other facets of ultra-endurance performance.
Don’t expect a six hour run to have the same benefit on your physiologic endurance or stamina as two three hour runs in the same week. It’s an over-simplification but surely gets the most salient features of physiologic adaptation illustrated to think of a six hour run giving three hours of training the body and three to other features of craft and skills while two, three hour runs in a week giving you six hours of training the body. In the first scenario, however, the six hour run, you get to practice aspects of craft that you cannot work on in two, three hour runs; the price you pay is additional recovery time without additional development - and possibly even some breakdown - of the body. This is one of the reasons that experienced ultra-marathon runners often get by without ever running substantial long runs - they don’t need to train craft anymore and they get the vast majority of physical training without very long runs.
Make a list of the aspects of running craft that you want to work on in your longest runs. Consider nutrition, hydration, footwear, clothing, other gear, psychology (such as confidence, focus, and trust), environmental conditions (such as night running and temperature variations). Then, next to each, list what works for you, what has not worked, and what you want to improve. Then estimate how much time you need to work on each of those and at what time in a long run might each present the opportunity to test changes? It’s probably not practical to indicate you need to get to hour 18 to test out nutrition because you’re not going to do an 18 hr training run - though you could enter a training race that would take you that long. Remember that it’s not only about the duration of any individual run but how many of them you need to figure out what’s working for you and develop both that knowledge and those skills that will serve you better in your upcoming goal events.
Clarify the reasons you're running beyond three hrs because those runs are physiologically costly. Appreciate that you are trading additional recovery time for deliberate practice and learning of craft, without much adaptable physiological benefit. Write out the plan, the reasons, and then take detailed notes during or immediately after the run. Plan tests of change for the next overly long run. You do not need many of these. Make the most of them but don’t make so many changes or test so many things on any single run that the results are confounded. For example, change only one - or maybe two - nutritional items, test a new prophylactic foot-taping method but not at the same time you try new shoes, and try positive third-person self-talk if you haven’t done it but not while chanting three new mantras and jamming to music your friend recommended.
My preference is to have athletes accomplish these in a mixture of training runs and training races. In my experience, most runners have more fun on an 8-hr training race than by themselves on such a long training run. Sometimes you can find friends to join you for all or part of a very long training run, which can help. But, sometimes, the solitude and aloneness of a very long, solo training run can be useful - the psychology, for example, is often more challenging.
I find that far too many athletes wait until they’re training for a particular race before developing the skills, practicing the crafts, and testing the options they’ll need. Be proactive. Races happen as checkpoints along your journey as a runner, they are not destinations. In my philosophy of long term training, an athlete varies training volume less than 25% throughout the year and there’s room for runs over 3 hrs duration to work on these things when you're not pressed for race preparation. In other words, many skills in running craft can be developed, practiced, and tested long before any race or event is on the horizon.