Four Training Zones Every Runner Needs to Know

Running seems like a simple sport. But once new runners start hanging around other runners, they start to hear about long runs, tempo runs, speed workouts, strides, hill workouts, and even the strange-sounding “fartlek.” They come to learn that experienced runners do different types of workouts at different times, and that coaches use all sorts of terms to describe runs.

Over time, coaches have organized the various different runs and workouts into groups, or zones. Within each training zone, you’ll find different types of runs and workouts to help build a desired type of fitness. Understanding the whys and hows of each zone is useful to tease out which workouts work best for you, and which workouts are ideal to prepare you for specific races.

I’m going to introduce you to the training system I use, which is comprised of four zones. I adopted these zones from exercise scientist David Martin, although I’ve renamed them because his naming system relied on physiology terms. My zone names reflect the aspect of fitness the runner would improve by running in that zone: (1) endurance, (2) stamina, (3) speed, and (4) sprint.

Zone One: The Endurance Zone

The bulk of a runner’s training happens within the endurance zone. The reason is that the bulk of the energy for running—including racing—comes from the energy systems that are improved with endurance training. Plus, endurance-zone running gradually builds an increasingly stronger runner’s body, so you can tolerate more and faster training in the future.

Endurance-zone runs are continuous runs that can last anywhere from 10 to 15 minutes to several hours. For most runners, these are your regular runs, where you go out and just cover distance (or run for time) at a “casual run” pace. Your breathing stays under control, and you can carry on a conversation when running in the endurance zone.

There are three types of runs within the endurance zone: easy runs, long runs, and recovery jogs. Easy runs are your daily comfortable miles, long runs are easy runs that extend more than 90 minutes, and recovery jogs are short, slow runs when you are very tired a day after a hard workout.

Zone Two: The Stamina Zone

The next zone is the stamina zone, or what some coaches call “threshold” training. As you run faster and faster, you cross a threshold where your body produces more lactic acid than it can remove, causing you to tire. Stamina-zone workouts are designed to help push this “lactate threshold” to a faster pace.

There are four types of workouts within the stamina zone: steady-state runs, tempo runs, tempo intervals, and cruise intervals. You can repeat the same type of stamina workout multiple times, but I find that doing a mix of the four different stamina-zone workouts is best.

Steady-state runs—also called “subthreshold runs” because the pace is slightly slower than the lactate threshold—are continuous runs lasting at least 25 minutes and as long as 75 minutes. Your effort rises to easy-medium, and your breathing gets a little faster yet is still mostly under control.

Tempo runs are slightly more intense efforts than steady-state runs, and they’re run right at the lactate threshold. They last between 15 and 30 minutes and are meant to be comfortably hard. Like the steady-state run, tempo runs are continuous efforts, prefaced with a thorough warm-up.

Tempo intervals are fast tempo runs broken into repeats with relatively short recovery jogs. They last between 8 and 15 minutes, with two to five minutes of jogging between each repeat.

Cruise intervals are essentially shorter and slightly more intense tempo intervals. They last three to eight minutes, followed by short recovery jogs of 30 seconds to two minutes.

I like to insert one to two stamina-zone workouts per week in the early weeks of a 5K or 10K training plan, before the runner transitions to speed-zone workouts as the race nears. Conversely, I focus on stamina-zone workouts in the last few weeks of a half-marathon or marathon plan, since stamina zone workouts are more race-like for longer races.

Zone Three: The Speed Zone

The speed zone is where you work on the maximum capacity of your aerobic system, also called maximum-oxygen uptake, or VO2 max. When experienced runners talk about speed work, this is often what they are talking about: repetitions at or around your VO2-max pace (your 5K race pace or slightly faster for most runners), with short recovery jogs in between.

Repeats in the speed zone usually last between 60 seconds and five minutes. Because the pace is faster, you must take a recovery jog either half the distance or the same amount of time as the fast repeat. So if you run a 1,200-meter repeat in five minutes, you would jog for about 600 meters, or for five minutes, to recover. These workouts enable you to maintain your speed over a longer period of time.

The “talk test” is a good way to know whether your effort is appropriate for the zone. In the endurance zone, you can carry on a full conversation, in the stamina zone, you can still speak full sentences. In the speed zone, the effort progresses to medium-hard and your breathing is elevated to the point where you can really only get out very short sentences or even just single words.

There are two types of workouts within the speed zone: track intervals and fartleks.

Track intervals are repetitions of specified distances, usually between 400 and 1,600 meters. They are often repeats of the same distance, e.g., running 400 meters 12 times at a 5K pace with a recovery jog of equal time. Another popular option is to step down in distance with each repeat—e.g., 1,600 meters, 1,200 meters, 800 meters, 400 meters—or work up, then down a “ladder” of distances.

You can also do speed-zone runs by time and effort in what is called a fartlek run. Fartlek is a Scandinavian word meaning “speed play,” and the originators used fartlek running as a way to get in a speed workout without the requirement of a marked track or course, using effort as the measure rather than pace. An example would be to run ten repetitions of one minute “on” (hard) and one minute “off” (easy).

Since speed-zone workouts are race-like for shorter events (less than 10,000 meters), I include a weekly track or fartlek workout as the race nears to get runners prepared for the specific physical and psychological demands of going fast. For longer races, I like to schedule occasional speed-zone workouts early in the training plan, to help race pace feel easier when runners start working on it a lot in the final few weeks of training.

Zone Four: The Sprint Zone

The final training zone is the sprint zone. Workouts in this zone help your top-end speed and consolidate your stride. The goal is to run very fast, let the body and mind recover, and then do it again. You get two important adaptations from sprint-zone training: first, you improve your ability to tolerate and remove lactic acid, and second, you improve your running form.

Like the speed-zone training described above, sprint-zone workouts are repeated hard efforts with recovery jogs in between. They differ by being even faster, shorter, and with longer recoveries.

There are two types of workouts in the sprint zone: sprint intervals and strides.

Sprint intervals (a.k.a. lactic-acid tolerance workouts) are repeats that last only 100 to 400 meters and are run at about your two-minute to eight-minute race-pace effort (a half-mile to mile race pace for most runners), with very long recovery intervals. You should take two to five times the duration, or one to two times the distance, of the fast running as a recovery jog before starting the next hard effort. For example, if you run 200 meters in 40 seconds for your hard interval, then you would jog for 1 minute 20 seconds to 3 minutes 20 seconds, or for 200 to 400 meters before beginning the next sprint.

The goal of sprint intervals is to flood the muscles with lactic acid and then let them recover. With practice, your leg (and mental) strength and your ability to buffer lactic acid will improve, allowing you to sprint longer. Weekly sprint intervals in the final few weeks of the training plan work great for track runners preparing for races shorter than 5,000 meters, where buffering lactic acid is particularly important to success.

Strides—also called wind sprints, pickups, striders or stride outs—are short, fast accelerations. Strides work to improve your sprinting technique by teaching the legs to turn over quickly.

We don’t want lactic acid to build up the way it does during sprint intervals, because lactic acid inhibits the nervous system and interferes with the neuromuscular adaptations that we want. Strides, therefore, last only 10 to 20 seconds, and you must jog easily for a minimum of 30 seconds and as much as a minute and a half to make sure your muscles are ready for the next sprint.

As you might imagine, the pace for strides is very fast—a one-minute to six-minute race pace (a 200-meter to mile race pace for most). Note that this is not all-out sprinting. The goal of strides is to run fast but always stay under control and focus on excellent running form. You can incorporate four to twenty strides during the middle of your run or at the end.

Strides have become my secret weapon for most runners, run two to three times a week year-round. Strides teach new runners how to run fast with excellent running form and set them up for doing stamina and speed-zone runs. Experienced runners also benefit, as strides continue to make stamina- and speed-zone runs feel easier; plus, they help hone a finishing sprint. And for older runners, strides are a way to gradually reinsert faster running while avoiding injury.

Excerpted and adapted from Running Nirvana: 50 Lessons to Elevate Your Running, by Greg McMillan.