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You can get in decent racing shape by regularly doing key sessions like tempo runs, long runs, and VO2 max intervals. But to really reach your potential, you need to emphasize different components of training at different times in your buildup to important races.
You need, in other words, to do periodized training. Below we’ll explain what periodization is, why it works, and how to apply it to your training.
What is periodized training?
Periodized training is structuring your training for a goal race so that on race day you’re at optimal fitness for the demands of that race.
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“Goal race” is a key part of the above definition. Periodized training is most appropriate when you’re targeting a specific distance on a specific date. That doesn’t mean your only race of a season is that target race; tune-up races are usually key elements of a periodized training block. But it does mean that everything in your training is done to bring you to peak readiness for a goal race, whether that’s a mile, a marathon, or any distance between. (Or shorter than a mile or longer than a marathon, for that matter.)
As we’ll see below, periodized training often consists of breaking a pregoal-race training block into three phases. In each phase, you have one or two primary training objectives. The training objectives in each phase build on each other so that you’re fully prepared for the specific demands of your event on race day.
For example, periodized training for a marathon might entail a first phase of building general endurance, a second phase of increasing long-run distances and improving your lactate threshold, and a third phase of integrating goal-pace efforts into long runs. This approach improves race-specific energy systems much more effectively than doing the same mix of overall mileage, length of everyday and long runs, and types of workouts week after week.
Periodized training is also better than focusing almost exclusively on running at goal pace for your target distance, for two reasons. First, periodized training better builds all the energy systems that contribute to peak fitness. Running a fast 5K, for example, obviously requires prowess at holding 5K race pace. But being able to hold that pace for more than a few minutes at a time demands good general endurance (built through long runs and overall mileage) and a good lactate threshold (built through tempo runs). A good 5K program, therefore, lays the groundwork in its early phases with lots of running at paces other than 5K race pace. Then, when it’s time to do more specific workouts at 5K pace, you’ve built the stamina to handle workouts and, ultimately, races, that require holding that challenging pace for several minutes.
Second, periodized training makes it easier to avoid physical and psychological staleness. For example, even if doing two or three workouts per week at 5K goal pace for several months were the best way to prepare you for a goal 5K, the chances of your surviving that training are slim. By race day, you would likely be hurt, or past peak fitness, or mentally fatigued. You might even be all three. Periodized training provides enough week-to-week variety, as well as variety within each week, to keep you physically and psychologically fresh.
Think of periodized training as raising your set point. In the marathon example above, something like a 14-miler at a moderate pace might be quite challenging in the second week of the first phase. Later on, the same distance at the same pace won’t take as much out of you, with the result that you can continue to do such runs while focusing on some other aspect of training, such as getting more efficient at goal race pace.
A bonus: Periodized training helps to simplify decisions when everyday life interferes with your training. Let’s say you’re in the second phase of the marathon buildup described above, and that a work crunch leaves you with time and energy for only three runs a week. You would then prioritize a good long run and a lactate threshold workout, such as a tempo run, and fit in a short, easy recovery run on the third day.
How to create a periodized training program
There are two big-picture ideas to keep in mind when building a periodized training plan.
First, your training should logically and gradually move toward more race-specific workouts, and you should logically and gradually extend the duration of those race-pace sessions. A good 5K program, for example, will have you start with occasional workouts of shorter reps, such as 400 meters, at your goal 5K pace. Over the several weeks of your buildup, race-pace workouts become more frequent, and the distance of the repeats in those workouts gets longer (usually topping out at mile repeats at 5K pace). Similarly, over the course of a marathon buildup, you do more frequent bouts of marathon-pace work, and those bouts get longer.
The second big-picture idea is that periodization is more about emphasis than exclusion. A good training program always includes a wide variety of paces and distances. Even when they’re a few weeks away from a goal 5K, top runners still do long runs and tempo runs.
Most periodized training programs have three phases, or training blocks, each from a few to several weeks long. The first phase tends to be the longest, such as the first six weeks of a 12-week 5K plan, with the remaining time split evenly between the second and third phases.
The first phase is generally devoted to building overall endurance by increasing weekly mileage and the length of long runs. (Remember, though, that a good training program includes workouts such as tempo runs and interval sessions throughout.) In the second phase, you generally maintain or increase the weekly mileage you peaked at in the first phase, while adding more intensity (usually by doing longer repeats in interval workouts or longer tempo runs).
The third phase’s focus is race preparation. Here, you generally drop your weekly mileage by 10 to 20 percent and focus most of your hardest work on longer efforts at goal race pace. In this final phase, true recovery runs become more important, because your hardest workouts are more draining. For example, early in a 5K program, you might do a workout of 10 to 12 400-meter repeats at goal race pace. That workout will probably tire you, but not exhaust you, and the next day you would probably feel fine on a standard run. Two weeks before your 5K, however, you might do a workout of three or four one-mile repeats at goal race pace. That workout is quite draining, and nothing more than a short jog is appropriate the following day, especially with your race coming up.
As noted earlier, periodization helps you know how to structure each training week in each phase. For each week, plan two or three hard sessions that contribute to meeting the goals of that phase. (Long runs count as a hard session.) Don’t be tempted to cram more than three key days into a week. It’s better to build your fitness gradually and feel like you’re absorbing your training than plateau or burn out or get hurt halfway through your buildup. If you have a history of injury or not recovering quickly from hard training, stick to two key sessions a week. A good middle ground for many busy recreational runners is to plan five key days in every two-week block, such as a VO2 max workout and a long run in one week, and a tempo run, a workout of short reps at mile pace, and a long run in the following week.
To see these principles of periodization applied in detail, see our training programs.
How to modify periodized training
Periodization was invented to have world-class athletes be at peak race-specific fitness on a date known months in advance, such as an Olympic final or the Boston Marathon.
That approach isn’t necessarily appealing to the many runners who can’t justify organizing their lives around a race, especially a non-marathon, that’s months away. Also, many recreational runners like racing frequently at a variety of distances.
If that’s you, you can still benefit from a form of periodized training. The idea here is to regularly do a good mix of key workouts (VO2 max, tempo runs, hill repeats, long runs, short reps at mile pace or faster, and long runs).
Then, when a particular race in the near future catches your fancy, shift your emphasis to a few weeks of more event-specific training. This approach has been used by some of the best runners in the world, such as Australian 5K record-holder Craig Mottram, who famously said he was never more than six weeks away from being able to break 13:00 for the distance.
Scott is a veteran running, fitness, and health journalist who has held senior editorial positions at Runner’s World and Running Times. Much of his writing translates sport science research and elite best practices into practical guidance for everyday athletes. He is the author or coauthor of several running books, including Running Is My Therapy, Advanced Marathoning, and Meb for Mortals. Scott has also written about running for Slate, The Atlantic, the Washington Post, and other members of the sedentary media. His lifetime running odometer is past 110,000 miles, but he’s as much in love as ever.
