European Journal of Applied Physiology

You’ve probably heard of the book 80/20 Running, perhaps even read it. But did you know that the original working title of this book was A High-Mileage Manifesto? I started writing it in 2013, a time when HIIT mania was in full bloom, CrossFit Endurance was making waves, and Run Less, Run Faster was the top-selling training guide for runners. Dismayed by these and other influences, I decided to push back in the best way I knew. It was only when I realized that the average runner can’t benefit from running more until they’ve first balanced their training intensities correctly—shifting from the typical 50 percent moderate-intensity routine to the 80 percent low-intensity approach of the elite—did A High-Mileage Manifesto become 80/20 Running.

Despite this evolution, I remain convinced that exercising a lot is a proven best practice in endurance training that not enough athletes at the nonelite level actually practice. Scientific support for this position keeps coming. The latest evidence arrives in the form of a study published in the European Journal of Applied Physiology. Japanese researchers surveyed 587 runners (all male, unfortunately) about their training prior to their participation in the 2017 Hokkaido Marathon. Intensity data were not included in this particular study. The researchers were specifically interested in identifying links between various volume-related parameters and marathon performance—and they found them.

Among runners who trained with equal frequency, there were significant correlations between monthly training volume, average run distance, long run distance, and marathon time. In other words, given two runners who each trained five times per week, the one who packed more miles into these runs tended to perform better on race day. Interestingly, though, when the researchers compared runners at different levels of monthly volume, there were no correlations between training frequency, average run distance, long run distance, and marathon time. This suggests that monthly volume matters a lot, and how one achieves it matters less. But it does matter some, for when the researchers looked at runners who had the same average run distance or long run distance, strong correlations were found between these variables and monthly volume and marathon time.

On the basis of their findings, the researchers concluded, “These results indicate that monthly training volume is the most important factor in predicting marathon time and that the influence of monthly training volume is only significant if the running distance per workout exceeded a certain level.” The lesson I draw from this study as a coach is that, if you want to race a good marathon, you need to run high-mileage consistently. Get your volume up to a high but sustainable level and keep it there.

Photo from

Perhaps I’ll get around to completing A High-Mileage Manifesto one day. For now, here’s the overview to a proposal I wrote for the book.

In 1945 Arthur Lydiard set out on a five-mile run that changed his life—and the sport of running—forever. The young track racer struggled to keep up with a much older man on that relatively short jaunt and came home humbled, realizing he was not nearly as fit as he’d thought he was. Sensing that the secret to running faster in races was to run farther in training, Lydiard gradually built his endurance to the point where he was able to easily run well over 100 miles every week, which was unheard of in those days. In 1953, Lydiard, now thirty-six years old, won the New Zealand Marathon Championship. Afterward he was inundated by requests for coaching from other runners.

At the 1960 Olympics in Rome, three athletes coached by Lydiard won medals (two of them gold). Suddenly the whole world was interested in Lydiard’s high-mileage training approach. Within a decade this approach had been adopted by virtually every elite runner on earth and was responsible for a drastic improvement in world records at all race distances between 800 meters and the marathon. Today the essence of Lydiard’s training system is still practiced almost universally by professional runners and by most collegiate runners and serious high school runners.

Curiously, however, the vast majority of runners who take up the sport as adults do not run high mileage and are not even aware that this training approach is regarded by every true expert as the necessary path to the full realization of any runner’s innate potential. Of course, the average recreational road racer with a full-time job and a family cannot be expected to run more than 100 miles per week as the professionals do. But it is bizarre that such runners are not even encouraged to run as much as they reasonably can. No other sport is bifurcated in this way, where competitive young athletes and recreational adult athletes are not even taught the same methods to improve.

The split occurred when the sport of running exploded in popularity in the 1990s and it has widened steadily since then. The rapid minting of new adult runners has created opportunities for new coaches to guide and train them. Almost without exception, the opportunists who specialize in mentoring adult recreational runners have little or no background in serious competitive running and were never indoctrinated into Lydiard’s high-mileage training approach. Knowing no better, these pseudo-experts base their own training systems not on high mileage but instead on “new” methods such as high-intensity intervals and technique fixing, which are not new at all but in fact were tried by past generations of elite runners and discarded as inferior.

This madness has to stop. Every runner deserves to know the best way to train. While high-mileage running may not be for everyone, the method that Lydiard perfected sixty years ago yields better results than any alternative even when scaled to fit the lifestyle of the average recreationally competitive adult runner. It’s a crime that this truth, known to all of the sport’s true experts, has been hidden from the masses by lesser authorities. A High-Mileage Manifesto is an overdue corrective that rediscovers the lost secret to running better and motivates runners who are not already enjoying its fruits to give it a try in the way that works best for them.

Written by Matt Fitzgerald, whose previous books include the bestselling Racing Weight and the award-winning Iron War, A High-Mileage Manifesto does not badger busy runners to run more than they really want to. Instead it makes Arthur Lydiard and his method the heroes of a story of triumph against long odds and of lasting survival in the face of wrongheaded challenges. In this way the book gently persuades readers to make their own choice to embrace high-mileage running, which truly can be tailored to work for any runner, as the meaning of “high mileage” is relative.

Like Fitzgerald’s past books, A High-Mileage Manifesto is intended above all to provide a captivating and satisfying reading experience for all runners who enjoy running enough to purchase a book on the subject. Readers will enjoy the author’s rich portrayal of Arthur Lydiard, history’s most iconic running coach, about whom far too little is known by most runners today. They will also gain a new perspective on the history of the sport as Fitzgerald traces the evolution of training methods from the nineteenth century to the Lydiard revolution to today. And they will have their minds blown by Fitzgerald’s limpid explanations of fascinating new science proving the superiority of high-mileage running in unexpected ways that almost no one yet knows about.

The book is organized as a linked set of narrative essays arranged in a loosely chronological order. Chapter 1 lays out the problem to be solved. The next several chapters take the reader on a journey of entertaining persuasion that follows the story of Lydiard’s great idea from its unlikely conception, through its astonishing world takeover and subsequent setbacks, to its ultimate vindication. The concluding chapter tells runners of all experience and ability levels everything they need to know to benefit from high-mileage running. By the time they get there readers will be keyed up beyond all expectations to do just that.

These are exciting times to be an endurance training geek. We seem to have entered a new period in which exercise scientists are taking the lead in coming up with innovative new workout formats. It makes sense. For many decades, humanity knew so little about how to train optimally for endurance performance that the majority of innovations simply had to come from folks in the trenches—namely coaches and athletes—throwing stuff against the wall and seeing what stuck. The role of scientists was to come along afterward and confirm that what seemed to work best in the real world really did, and to explain why.

In the past several decades, however, the pace of innovation has slowed greatly, a sure sign that we’ve gotten pretty close to the point where training methods cannot be improved any further. Being close to this point is not the same thing as being at this point, however. There’s still room to innovate, but it’s more a matter of fine-tuning now; the days of radical tacking are gone for good. A different sort of expertise is required for this task—a sort that scientists are showing themselves to be well suited for.

Specifically, exercise scientists have lately been using their knowledge of why some training methods work better than others to create workout formats that work better still. True to their nature as scientists, they are very focused on measurable fitness variables such as VO2max, Their way of innovating, therefore, is to in seek out ways to enhance he fitness benefits of training without simply making workouts harder. Most of the new workout formats I’ve seen in the past few months have been designed specifically to boost the amount of time an athlete spends above 90 percent of VO2max in an individual session—known to be an especially potent fitness-boosting stimulus—as compared to a traditionally formatted workout of equal workload and/or perceived difficulty.

The latest offering comes from a trio of researchers working at the University of Udine, Italy. Their idea was to design an interval session featuring high-intensity work bouts that steadily decreased in length throughout the session. The rationale behind this design, as noted in a study published in the European Journal of Applied Physiology, was that past research had shown that longer intervals at high intensity allow athletes to reach VO2max quickly, whereas short intervals allow them to continue longer before reaching exhaustion. Would a set of decreasing intervals offer the best of both worlds, comparing favorably to a set of long intervals and a set of short intervals in these respects?

To find out, the researchers had 12 cyclists complete the following three workouts:

Short Intervals Long Intervals Decreasing Intervals
0:30 @ high intensity/0:20 @ low intensity repeated to exhaustion 3:00 high/2:00 low repeated to exhaustion 3:00 high/2:00 low

2:00 high/1:20 low

1:00 high/0:40 low

0:45 high/0:30 low

0:30 high/0:20 low repeated to exhaustion


In all three workouts, the high-intensity efforts were performed at the highest power output each individual cyclist could sustain for 5 minutes and were repeated to exhaustion. Each subject completed all three workouts in random order on separate occasions. On average, the cyclists lasted 13 minutes and 20 seconds and spent 5 minutes and 12 seconds above 90 percent of VO2max in the decreasing intervals workout, compared to 11:54/3:02 in the short intervals workout and 11:04/2:59 in the long intervals workout.

The researchers concluded that “despite the higher stimulation of VO2, the rate of perceived exertion and the other physiological parameters at the end of the exercise were not different compared with long- or short-interval HIIT, suggesting that [the decreasing intervals format] was not more demanding. In light of the favorable or similar physiological and/or perceptual

responses to [decreasing intervals] compared to the other protocols and given the improved capability to prolong the time close to VO2 peak, it could be used as a preferable method to elicit similar or greater physiological adaptations.”

Sound like decreasing intervals are simply better, right? And if so, they should completely displace short- and long-interval VO2max sessions in the training process, right? Not so fast. As interesting as it is, this study falls far short of constituting a total contextual evaluation of these three interval formats. It’s important not to lose sight of the fact that doing five 3-minute intervals at your 5-minute maximum power is a different experience from doing decreasing intervals. The suck that you feel toward the end of the former is more similar to the suck you’re going to experience in races, and I think there’s a lot to be said for that. Therefore I have no intention of expunging traditional VO2max interval workout formats from the training I prescribe for the athletes I coach or for myself.

Still, I’m excited about decreasing intervals, and indeed I’ve already begun to prescribe them to athletes I coach and to practice them in my own training. They can be done either on a bike, as originally designed, or as a run. If you do them on a bike, complete the high-intensity intervals at 117 percent of the average power output you achieved in your most recent 20-minute FTP test. So, if your 20-minute power is 293 watts, do the high-intensity intervals at (293 x 1.17 =) 342 watts. If you choose to do decreasing intervals as a run, complete the high-intensity intervals at maximal aerobic speed (MAS), which is the fastest pace you could sustain for about 6 minutes.

Note that the subjects in the study I described performed decreasing intervals to the point of exhaustion solely for the sake of determining which of the three formats allowed them to continue the longest. When doing decreasing intervals as a part of your normal training, you may want to stop short of exhaustion. Specifically, I suggest you complete the sequence just once on your first try to get a feel for it. If you’re game for a tougher challenge, the next time you do decreasing intervals, go back to the top of the sequence immediately after the 20-second recovery and continue until you can no longer hold power on the bike or until you’ve “had enough,” if you’re running. On average, the study participants were able to complete only one full circuit plus part of a second 3-minute effort, so don’t expect the fun/suffering to last too terribly long.

I am not an exercise scientist, but I do have a strong interest in the science of endurance exercise, and every once in a while I speculate on the kinds of questions exercise scientists like to explore experimentally. For example, back in 2004 I found myself wondering if training in a hot environment might improve endurance performance in a temperate environment, sort of like how training at high altitude improves endurance performance at low altitude. My curiosity led me to put the question to famed sports science researcher Tim Noakes, who, in his prompt and courteous reply, dismissed the idea as “too bizarre to consider.”

Six years later, sweet vindication came my way in the form of a study appearing in the Journal of Applied Physiology under the title “Heat acclimation improves exercise performance.”

Led by Santiago Lorenzo of the University of Oregon, the study involved 20 highly trained cyclists, who were asked to complete a performance test in temperate conditions on two occasions separated by 10 days. Between the tests, all 20 cyclists completed a prescribed training program, but 12 of them did it in a controlled, hot environment (100 degrees Fahrenheit) while the other eight performed their workouts in the same temperate conditions (55 degrees) as the performance tests. The 12 cyclists who underwent heat acclimatization improved their performance in the temperate performance test by a massive 7 percent, while the control group showed no improvement.

Lorenzo’s team attributed the performance-boosting effects of heat acclimatization on endurance performance in cool conditions to improved efficiency in heat dissipation and increased blood volume. They also found evidence that it caused some changes in muscle cell enzymes, which may have contributed to the effect as well.

Several subsequent studies have mined the same vein vein more deeply. The most recent study on heat training in endurance athletes, published in the European Journal of Applied Physiology, offers important guidance on how best to use this method in real-world settings. Led by Mark Waldron of Swansea University, the experiment aimed to track the time course of adaptations to heat training.

Twenty-two male cyclists were separated into experimental and control groups. Members of the experimental group cycled indoors at 100 degrees Fahrenheit while members of the control group did an equal amount of cycling at 68 degrees. Waldron’s team measured VO2max in both groups before the intervention, on days five and ten of the intervention, and on days one, two, three, four, five, and ten afterward.

The results are interesting. Both groups exhibited an initial decrease in VO2max during the 10-day training period that was followed by a rebound beyond baseline afterward. The peak increase was higher in the heat-training group, but not until four days after the last heat-training session, with some variation between individuals. VO2max then began to trend toward decline in this group, though the amount of decline that occurred between day four to day 10 post-acclimation did not reach statistical significance.

In a nutshell, these findings suggest that if you’re going to use heat training to increase your endurance performance, you need to time it to end about four days before you race. This means that your heat training is likely to overlap with your pre-race taper. Is this insane? It might sound so, but there’s a difference between sound and substance. While training in 100-degree heat might be uncomfortable, it’s not going to kill you, and which would you rather do: 10 days of heavy, peak training in 100-degree heat or 10 days of lighter, taper training?

That being said, I don’t recommend that you try heat training for the first time before an important race. Instead, test it out early in a training cycle to see how it affects you. It won’t be wasted even then, because if it works it will give your subsequent training a nice boost.

I can’t help but wonder if doing one hot workout every week or so throughout a training cycle might have similar benefits. Personally, I would find this approach easier to manage. Heat training could then be used in much the same way carb-fasted workouts are, and perhaps the two methods could even be combined to minimize the number of training days that need to be set aside as “special” sessions. Can I get a real exercise scientist to look into this?

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