This post is part 2 in a series concerning my spring marathon training plan. To read part 1, click here.

Previously, I wrote about why I decided to follow an Arthur Lydiard-style training plan influenced by the Maffetone Method while training for my spring marathon, the Inaugural Queens Marathon. Today, I will describe the first phase of that training plan—aerobic base training—and how it fits into the overall training scheme. As I’m not an exercise scientist or running coach, this post represents knowledge I’ve gained from reading various books, Internet articles, conversations with running coaches, and personal experience. I would strongly encourage you to read further on this subject if it interests you.

Aerobic Base Training

When coaches discuss a runner’s training for an endurance event, they often mention the runner’s “fitness.” For example, before heading out on a 10-mile group training run for the NYC Half Marathon a couple weeks ago, a well-known local running coach told the group, “Don’t worry if you can only run 5 miles today. You’ve got 12 weeks to get fit for the NYC Half.” Why would he emphasize the concept of “being fit?”

For runners, “being fit” means having a well-developed aerobic system (i.e., well-developed endurance capabilities). A runner’s aerobic fitness is the number one factor in determining how well that runner will race on any given day. So, what exactly is aerobic fitness, and how does a runner develop it?

Defining “Aerobic Fitness”

By way of background, the body produces energy through two different but linked systems: the aerobic system, and the anaerobic system. The aerobic system utilizes oxygen to break down fats and glycogen (stored sugars) in order to fuel our cells during exercise. It is the dominant energy system for efforts at or below about 85% of an athlete’s maximum heart rate (NOTE: Maximum heart rate can be roughly calculated by subtracting your age from 220). It utilizes a greater percentage of fat than glycogen and, generally, the less intense the effort, the larger percentage of fat the body will burn during a workout.

The anaerobic system gets activated when a person has become oxygen-deficient—that is, when the amount of oxygen he is consuming can no longer produce enough energy to sustain his effort. Oxygen deficiency typically arises when a person is training or racing at about 90% of his maximum heart rate. The anaerobic system operates without oxygen, and utilizes almost exclusively glycogen. As a result, the body cannot sustain anaerobic efforts for extended periods of time. Why? Because the body is capable of storing only 2,000-2,500 calories of glycogen at any given time, compared to over 40,000 calories of fat. As such, sustained hard efforts burn up glycogen quickly, and a runner will “hit the wall” or “bonk” once he has used up all of his glycogen stores. Further, because the ratio of sugar to fat utilized in energy production decreases as a runner’s heart rate increases (that is, the runner’s body utilizes more sugar), a runner will also deplete his glycogen stores after a hard, sustained aerobic effort. For example, first-time marathoners often “hit the wall” around miles 18-20 after around three hours of sustained aerobic effort.

Based upon the foregoing, we can conclude the following two things: First, “aerobic fitness” is the body’s ability to utilize oxygen to produce energy. And second, in any given endurance event (defined as any event 800 meters or longer), a runner’s aerobic fitness determines how long he can sustain a hard effort over a given distance. Therefore, training one’s body to utilize oxygen efficiently and to run faster at lower efforts (that is, lower heart rates) is critical to developing speed over long distances.

In other words, one’s aerobic fitness is the most important factor in determining one’s speed in any given event.

(NOTE: This does not mean that anaerobic development is unimportant or unnecessary: quite the contrary. In fact, anaerobic development is the second most important factor in determining how well a runner will perform in a given race. Further, a runner who fails to develop his anaerobic capacity will not perform his best (I will cover this in my post about Phase 3: Anaerobic Training). But for now, remember that aerobic fitness is the key to getting faster in any endurance sport, and learning how to properly train the aerobic system will help any runner improve his racing times.)

Why An Aerobic Base Period?

If you’ve ever researched marathon training plans, you’ve probably found plans spanning 12-20 weeks that look like this: for beginners, 3-4 runs per week at shorter distances, plus an ever-increasing long run on the weekend; for intermediate runners, 3-4 runs per week at slightly longer distances, some hills and speedwork, and a weekly long run; and for advanced runners, multiple days containing hills and speedwork, some easy workouts, some workouts at marathon or half marathon pace, plus a weekly long run with some miles at marathon pace. While these plans cater to runners of different abilities (and likely help people achieve their goals), they lack context: Why do runners of different abilities engage in different types of training?

The answer is simple: Advanced runners have built an aerobic base. By building an aerobic base—that is, developing the ability to utilize oxygen more efficiently to break down fat and glycogen to produce energy and, therefore, to sustain harder efforts at lower heart rates for a longer period of time—these advanced runners have greater access to anaerobic development. In other words, a runner’s anaerobic development is dependent on how well-developed his aerobic system is. Therefore, in order to maximize anaerobic development, one must have a well-developed aerobic system.

(NOTE: Another benefit of an aerobic base period is that a runner can increase speed while running at relatively slow paces with a low risk of injury. Harder running such as intervals and racing increases the runner’s risk of injury, so a long base period has the added benefit of developing speed and strength with a lower risk of injury. In other words, it prepares the musculature for harder efforts later in the training cycle).

How to Develop the Aerobic System

To train the aerobic system—that is (once again), to develop one’s ability to utilize oxygen more efficiently to break down fat and glycogen to produce energy and, therefore, to sustain harder efforts at lower heart rates for a longer period of time—a runner needs to train at an “aerobic pace,” which essentially means a pace below or well below “lactate threshold.” “Lactate threshold” is the pace at which the runner’s body begins to accumulate lactic acid—the byproduct of anaerobic energy production—at a rate faster than the body can break it down and expel it from its cells. The body can break down and use small amounts of lactic acid to produce additional energy. Unfortunately, once lactic acid builds up faster than the body can break it down, it disrupts the PH levels of the body’s cells, which causes destruction of the cells and, in turn, muscle fatigue and the feeling of hitting the wall.

What this means, then, is that hard efforts early on in the training cycle lead to the breakdown of the runner’s body, and can disrupt aerobic development. As such, an almost paradoxical relationship exists between fitness and racing: A runner must develop his aerobic fitness—the number one factor in determining how well he can race—only to destroy that fitness through anaerobic development (a necessary step in proper training) and racing.

An example from my own life: At my peak during my NYC Marathon training, I could run a mile at my Maffetone maximum aerobic heart rate (described below) of 1444 beats per minute in 6:55/Mile. After racing the Bronx 10-Mile, Staten Island Half, NYC Marathon, and NYRR NYC 60k in a seven-week period, my maximum aerobic pace dropped to 7:23/Mile as measured by the MAF test, a method for measuring one’s aerobic fitness. Only after two months of rest and near-exclusive aerobic training have I gotten my pace back to 7:00/Mile.

What this means, long-term, is that a runner who trains hard for a goal race will use up many of his aerobic gains in the lead-up to, and the actual, goal race. Thus, once the goal race is completed and the next goal is set, it will be necessary for the runner, if he wishes to continue his development, to start aerobic base training anew for the next race.

Aerobic Pace, as Defined by Lydiard and Maffetone

So, if a runner is supposed to train his aerobic system by running at an “aerobic pace,” how do we define that pace? Every coach seems to have his own definition.

Lydiard

Lydiard, for example, suggests that in order to develop a runner’s aerobic system, he should run at a pace that leaves him feeling “pleasantly tired” at the end of the run. While Lydiard never quantifies “pleasantly tired,” he indicates that a runner can determine that pace through trial and error by running on out-and-back courses and timing the run. If the second half takes longer than the first, then the runner’s initial pace was too fast. Ideally, then, an appropriate Lydiard-based aerobic pace is one at which a runner could run both halves of any particular run in the same amount of time, and end that run feeling “pleasantly tired.”

Based upon this, Lydiard recommends at least 3 long runs per week: 2 runs of about 1.5 hours each, and 1 run of 2+ hours, at the one’s “pleasantly tired” pace. He also recommends performing some tempo runs below lactate threshold, adding strides at the end of runs (for example, 4 x 100 meters of hard effort followed by extended recovery periods at the end of an otherwise steady state aerobic run), and adding as many additional miles at or below “pleasantly tired” pace.

So, an ideal Lydiard base-training week might look something like this:

• Monday: 1.5 hour run at PT pace
• Tuesday: Easy run with 4 x100 strides
• Wednesday: 5-10k tempo run at harder-than-PT pace but below lactate threshold
• Thursday: 1.5 hour run at PT pace
• Friday: Easy run with 4 x 100 strides
• Saturday: 2+ hour run at PT pace
• Sunday: Easy run with 4 x 100 strides
• Plus: As many other other runs as possible at or below the “pleasantly tired” aerobic pace

In his experience, Lydiard found that he and his athletes performed best when running approximately 100 miles per week at “pleasantly tired” pace plus as many miles at or below “pleasantly tired” pace as time would allow. He indicates that extra miles accumulated even with 15 minutes of jogging are beneficial. Of course, he instructs runners to run within their capacity, so a week of 20, 30, however many miles is acceptable as long as the runner does not push too hard.

Maffetone

According to Maffetone, one’s maximum aerobic pace is determined through his “180 Formula.” Take the number 180 and subtract your age from it. Then, adjust that number based upon a number of factors, including whether you’ve recently been injured, whether you get sick more than twice throughout the year, whether you’re new to running or a veteran, and whether you’ve seen improvement through using Maffetone’s formula. Then, when performing an aerobic run, keep your pace at or below your maximum heart rate, preferably in a range of your maximum aerobic heart and ten beats below (that is, your “maximum aerobic heart rate range”).

So, an ideal Maffetone week would look something like this: As many runs as possible within one’s maximum aerobic heart rate range.

Ultimately, both Lydiard and Maffetone indicate that running as close to one’s “pleasantly tired” pace or maximum aerobic heart rate most efficiently develops one’s aerobic system. While slower running will aid in development, such development will take more time. Further, both advocate for aerobic base periods that last as long as possible. Thus, if a runner has six months (26 weeks) to train for a particular race, the first 12 of those weeks should be dedicated to aerobic base training, and the following weeks dedicated to the additional phases of training (Hills/Leg Speed 4 weeks, Anaerobic Development 4 weeks, Sharpening 4 weeks, Freshening Up/Tapering 2 weeks).

Putting it All Together

Phew. That’s a lot, right? Here’s what I took from all this information, and how I applied it to my training.

First, while I trained for the NYC Marathon almost exclusively with the Maffetone Method, I felt that I might have outgrown it. I had built a solid aerobic base through the marathon training, and wanted to see if I could push harder. Second, almost every article I read and every coach I consulted indicated that incorporating more intense runs (below lactate threshold, of course) into a base-building phase would augment a runner’s aerobic development. As such, I decided to develop my base-building phase as described below:

First, I calculated my maximum aerobic heart rate and range as determined by Maffetone’s 180 Formula (144: 180 – 31 = 149, minus 5 because of my injury last year = 144 beats per minute, maximum aerobic heart rate range of 134-144 beats per minute). I also calculated my maximum heart rate using the popular 220 – age formula (220 – 31 = 189 beats per minute).

Second, I took the Lydiard skeleton and attempted to do at least three long runs a week, a tempo run, and as many other runs, bike sessions, and pool sessions as possible. When the schedule called for a run at an aerobic pace, I tried to keep my heart rate in my Maffetone range, in large part because Lydiard’s “pleasantly tired” metric mirrored how I felt after most Maffetone-style runs. When a run called for a harder effort below lactate threshold, I tried to keep my heart rate below 160 beats per minute, which equals about 85% of my roughly-calculated maximum heart rate. I also added strides at the end of many runs. You can see how I executed this plan from November 16, 2015 to January 24 here.

I did not follow the training advice perfectly. On two occasions I gave all-out efforts: first, in an unofficial 3.15-mile race (slightly longer than a 5k), and at November Project NYC PR day, a difficult 3.4-mile course. Outside of these 6.55 miles, the only hard efforts I did during this period were during strides at the end of runs, and the occasional tempo run. Thus, I feel good about this phase of my training. And, as I indicated above, I improved my maximum aerobic pace to 7:00/Mile from 7:23/Mile, which is a demonstrable gain in aerobic fitness.

In my next post, I will discuss Phase 2: Hills and Leg Speed.

Happy running, everyone!