A marathon plan built on volume and threshold
Pete Pfitzinger's method, set out with Scott Douglas in Advanced Marathoning, builds marathon fitness mainly through weekly volume, a second long-ish run in midweek and regular lactate-threshold work. Faster VO2max sessions and marathon-pace runs are added in smaller, well-placed doses, and the build finishes with a three-week taper. The plans are organised by mileage band and run for 18 or 12 weeks. They suit runners who already handle consistent volume and want a structured, demanding build towards a time goal.
Worth saying early: for nearly all runners, running more, consistently, is the big lever, and the details of any published plan are second-order. The mileage bands, session types and paces below describe one well-regarded way of organising that running. They add the most for runners who already hold steady weeks of volume.
Key takeaways
The plans come in four mileage bands (up to 55, 55–70, 70–85 and more than 85 miles a week) and in 18- or 12-week versions. Pfitzinger recommends the 18-week schedule for most runners.
Every schedule moves through four mesocycles: endurance, lactate threshold plus endurance, race preparation, and taper.
The medium-long run of 11–15 miles (18–24 km) in midweek is the signature session. It reinforces the long run without demanding the same recovery.
Lactate-threshold pace, roughly what you could race for about an hour, is the reference point for most of the other intensities in the system.
Marathon-pace runs are used sparingly. Pfitzinger's own coaching material suggests two or three over 12 weeks.
The entry requirements are real. The 55–70 mile plans assume you're already running around 45 miles (72 km) a week before week one.
Where the method comes from
Pfitzinger ran the marathon for the United States at the 1984 and 1988 Olympics and later worked as an exercise physiologist and coach. Advanced Marathoning first appeared in 2001. The third edition followed in 2020, and the fourth edition, now in full colour with expanded guidance on adjusting the schedules and on heart-rate training, was published by Human Kinetics in July 2025.
The book starts from the physiology of the event. It lists the attributes that separate good marathoners: a high lactate threshold, large glycogen stores and good fat use, running economy, a high VO2max and the ability to recover quickly. Each type of run in the plans targets one or more of these, and the schedules are the practical way of dosing them across a build.
The eight types of run
Each workout in the schedules belongs to one of eight categories. The pace and heart-rate ranges below come from Pfitzinger's own presentation material and from summaries of the book. Less fit runners sit at the lower end of each heart-rate range and well-trained runners at the upper end.
Run type | Typical length or format | Intensity |
|---|---|---|
Long run | 16 miles (26 km) or longer | 10–20% slower than goal marathon pace; 74–84% of max HR |
Medium-long run | 11–15 miles (18–24 km) | Same guidance as the long run |
Marathon-pace run | A long or medium-long run with most miles at goal pace | Goal marathon pace; 79–88% of max HR |
General aerobic run | Up to 10 miles (16 km) | 15–25% slower than marathon pace; 70–81% of max HR |
Lactate-threshold run | At least 20 minutes, often 4–7 miles of tempo after a 2–3 mile warm-up | About 15K to half-marathon race pace; 82–91% of max HR |
Recovery run | Relatively short | The slowest runs of the week; below 76% of max HR |
VO2max intervals | 600–1,600 m repetitions | About 5K race pace; 93–98% of max HR |
Speed | Strides of 50–150 m | Fast and relaxed |
Two details in this table shape how the plans feel in practice. Long runs have a pace range with a direction: Pfitzinger describes starting slowly, reaching about 20% slower than marathon pace after the first few miles and finishing around 10% slower. On that guidance, a 22-mile run takes roughly as long as the marathon itself. And recovery runs carry an upper limit on effort, because running them too hard is what erodes the quality of the next hard day.
How a build is structured
The four mesocycles
Each schedule is split into four phases. The first builds endurance through volume and the long and medium-long runs. The second adds regular lactate-threshold sessions while the long-run work continues. The third, race preparation, brings in VO2max intervals, marathon-specific runs and tune-up races of 8–15 km. The fourth is the taper and race. A five-week post-marathon recovery schedule can follow any of the plans.
The 12-week schedules keep the same four phases but shorten each one. Pfitzinger is direct that this compresses the preparation, which is why the 18-week version is the default recommendation.
What a typical week looks like
A schedule he published in Runner's World, peaking at about 70 miles (113 km) a week, shows the pattern. Monday is rest or cross-training. Tuesday carries the quality session, for example 9 miles with 4 miles at 15K to half-marathon pace. Wednesday is a medium-long run of 12–14 miles. The rest of the week mixes recovery runs, general aerobic runs with strides and a long run at the weekend. In race preparation, the weekend run becomes marathon-specific, such as 17 miles with 14 at marathon pace, and Saturday tune-up races appear.
The point to notice is how much of the weekly load sits in two runs. With a long run and a medium-long run in the same week, a runner at 60 miles (97 km) can cover close to half the week's distance in those two sessions. That is the main way the plans build endurance without adding more long runs.
Recovery weeks and the taper
Recovery weeks recur during the build. Pfitzinger's general rule of thumb, from his Runner's World writing, is to run 60–70% of the previous week's mileage and drop the intense sessions.
The taper lasts three weeks. In that Runner's World schedule, weekly volume falls from 68 miles to 56, then 46, then 30 miles in the six days before the race. Intensity stays in, in smaller doses: strides, a short VO2max session ten days out and a final 8–10 km tune-up race two weeks before the marathon. His Runner's World guidance gives the taper as roughly 70–80% of peak mileage three weeks out, 50–60% two weeks out and about 30% in the final six days.
Lactate-threshold pace as the anchor
On his coaching site, Pfitzinger describes lactate-threshold pace as the single best predictor of race pace from 8 km to the marathon, and the other workout paces are set relative to it. For experienced runners it is roughly the pace you could race for 45–60 minutes. For fast non-elite runners that's close to 15K race pace, and for runners whose 10K takes 50–65 minutes it is very close to 10K pace. His presentation material adds that sub-four-hour marathoners tend to race 15–30 seconds per mile slower than their threshold pace.
That gives the system a useful internal check. If your threshold sessions at the prescribed pace feel like races, or your heart rate sits above about 91% of maximum, your estimate of threshold pace is probably too ambitious, and the marathon goal built on it may be as well.
Where it sits next to other systems
The method shares ground with the other marathon systems we've covered. The Hansons cumulative fatigue method also relies on frequent running and steady-state work, and it caps the long run lower and leans more heavily on marathon-pace running. Renato Canova's marathon system moves much more of the late build to work at and around race pace. Pfitzinger keeps a larger share of the build at aerobic and threshold intensities and treats marathon-pace runs as a periodic rehearsal.
Who the plans fit
Runners who already have the volume. The schedules assume a starting base. The up-to-55 plans ask for at least 25 miles a week before you begin and a comfortable 12-mile long run in the previous month. The 70–85 plans ask for about 55 miles a week.
Runners chasing a time. Pfitzinger writes that the plans are for runners who want to race the marathon as hard as they race shorter events. The sessions assume motivation and a fairly predictable week.
Runners who can fit a midweek medium-long run. A 12–15 mile run on a Wednesday takes close to two hours for many runners. If that won't fit, the structure loses one of its main supports.
Runners willing to adjust. The fourth edition expands the guidance on moving sessions around. A schedule written day by day is a template, and missed days, illness and heat all call for changes the printed plan can't make for you.
What we know, and what we're inferring
The run categories, mileage bands, the 18- and 12-week formats, the four mesocycles, the entry requirements and the purpose of each session are documented in Advanced Marathoning and in Pfitzinger's own coaching material. The fourth edition (Human Kinetics, 2025) is the current edition. We have not read its full text, so some specifics here come from the third edition, its published excerpts and Pfitzinger's Runner's World articles.
Some figures differ slightly between sources. Long runs are defined as 16 miles or more in summaries of the book and 17 miles or more in his Runner's World plan, and the medium-long range is given as either 11–15 or 11–16 miles. Taper percentages also vary a little between his articles and his published schedules. Treat these figures as ranges.
The observation that the long and medium-long runs together carry close to half of a 60-mile week is our arithmetic from the published schedules, and it will vary from week to week.
Keeping the plan in proportion
A Pfitzinger build has real internal logic, and for nearly all runners the basics still carry most of the improvement: week after week of running, at a volume the body absorbs. The split between medium-long runs, threshold sessions and marathon-pace rehearsal refines a build that already has that consistency behind it. If a week has to change, the rhythm of regular running is worth protecting first.
Where kaizen fits
A printed Pfitzinger schedule assumes every week goes as written. kaizen quantifies the training load you're actually completing, knows your current fitness from it and sets weekly targets towards your goal marathon, then adapts when a week goes sideways. If you're partway through a Pfitzinger build, open kaizen on iOS or Android and compare your fitness with the goal pace your plan is built around.
