Marathon Interval Training: How To Add It To Your Marathon Prep

Intervals for speedwork are a key part of marathon training.


Adding interval training to your marathon training plan is one of the best ways to improve your fitness level and prepare for your marathon race, even for beginners.

Experienced runners trying to improve their marathon time or who have a specific goal time for a race day should certainly consider adding marathon interval training workouts to their marathon build-up.

However, knowing the best types of speed work or running intervals to add to a marathon training plan can be overwhelming for beginners and experienced runners alike.

Should you run intervals at goal marathon pace, or should you be doing speed workouts that are significantly faster, such as 5k pace, V02 max pace, or even a faster pace?

How often should you do easy runs versus speed work when doing marathon or half marathon training?

In this speed work guide, we will discuss what marathon interval training for runners looks like, the benefits of adding speed work to your marathon training plan, and the best types of interval workouts to do in your marathon build up based on your fitness level and goal pace.

A person running on a track.

What Is Marathon Interval Training?

Before we look at specific speed workouts to try it is helpful to discuss what we mean by speed work for marathon training.

Basically, “speed work“ is an umbrella term that refers to any running workout you might do that is run faster than an easy run pace. 

Most speed workouts include a warm-up, some type of interval training or faster running, and then a cool down.

Therefore, we can think of a speed workout as a training run that is more dynamic than just going out the door and running at a steady effort for the duration of your entire run.

Interval training is a specific type of speed work that involves running at a faster pace for a specific distance or time.

For example, an interval workout for a half marathon runner might involve 6 x 1,000 meters at 5k pace.

While interval workouts are now commonplace in training programs for middle-distance and long-distance runners, interval workouts have only been widespread in running plans since the 1950s, after runner Emil Zatopek implemented this revolutionary style of training.1Billat, L. V. (2001). Interval Training for Performance: A Scientific and Empirical Practice. Sports Medicine31(1), 13–31. https://doi.org/10.2165/00007256-200131010-00002

‌Emil Zatopek’s training style helped him break 18 world records and win five Olympic medals, and most running plans today still rely on the concepts introduced by this middle-distance runner.

Runners on a track.

Why Is Interval Training Good for Marathon Runners?

There are several benefits of interval training for half marathon runners and marathon runners.

Unfortunately, marathon runners often assume that they don’t need to do any interval training or speed workouts because they are going to be running continuously for upwards of 3 to 5 hours or more for their race and therefore do not need to work on running faster.

However, there are a number of important benefits of doing interval workouts even for half marathon training and marathon training:

  • Can help build strength in your muscles, tendons, joints, connective tissues, and bones. When you are running faster, you are applying greater forces and stresses through your musculoskeletal system.
  • Can decrease the risk of injury by strengthening the structures as mentioned above and also because running at different paces helps vary the stresses placed on your body and the nuances of your running form. This decreases the highly repetitive nature of running tons of miles in a marathon training build-up, potentially decreasing the risk of overuse injuries.
  • Can help you feel more comfortable at your goal race pace.
  • Can increase your VO2 max by improving the delivery, extraction, and utilization of oxygen.
  • Interval workouts can improve your running economy.2Barnes, K. R., & Kilding, A. E. (2014). Strategies to Improve Running Economy. Sports Medicine45(1), 37–56. https://doi.org/10.1007/s40279-014-0246-y
  • Interval training during a half marathon training plan or a marathon training plan can help you stay sharp and fast for shorter races, so that you can also see improvement in your 5k pace.
  • Adding different types of training runs add variety to your marathon workouts to help prevent boredom.
A person running on a track.

What Are the Best Workouts for Marathon Training?

Choosing the best types of speed work for any given runner depends on your fitness level, where you are in your marathon build-up, your goal pace, and the overall architecture of the marathon training plan you have been following.

Here are the primary types of interval workouts to include in your marathon training or half marathon training plan:

#1: Yasso 800s

There are different types of interval training workouts for marathon runners.

One of the most popular and classic interval workouts for marathon training is the Yasso 800s workout. The Yasso 800m workout is said to be a good predictor of your marathon finish time.

This marathon training workout was created by Bart Yasso, the former Chief Running Officer at Runner’s World and one of the most famous running coaches in early marathon training programs.

The goal of the Yasso 800s running workout is to build up to 10 x 800m at a running pace or finishing time where the minutes and seconds are the same as your goal marathon time in hours and minutes.

For example, if your goal time in the marathon is 4 hours, 

Your goal pace for each 800m repeat would be four minutes, and you would take four minutes of recovery between each one.

In contrast, if you have a goal marathon finish time of 3:10, you would run each of the Yasso 800m repeats in 3 minutes and 10 seconds.

The recovery after each track interval is equal to the time it takes to run the hard intervals.

Early in your marathon training plan, you might start with just 4 to 6 Yasso 800s, but as you progress through your 12 to 16 week marathon training plan, you would progressively add additional intervals at goal pace until you are able to do 10 x 800m.

Many marathon runners and running coaches swear by this interval workout and say that it is not only great for pacing and building aerobic fitness, but it also does seem to be a decent predictor of your finish time on race day.

People running on a track.

#2: VO2 Max Interval Workouts

Advanced runners or those who are looking to run a specific marathon goal pace can benefit from incorporating VO2 max interval sessions into their marathon training build up.

These interval workouts involve running different distances on the track at your VO2 max pace in order to stimulate physiological adaptations that hopefully improve your VO2 max, running economy, and anaerobic capacity.

For example, you might do 5 repetitions (reps) of 1000m, which is 2.5 laps of the track, at 95% of VO2 max pace.

Jack Daniels, one of the most renowned running coaches, suggests that in the absence of knowing your true VO2 max, well-trained runners can use their 3k running pace or a running speed that you can hold for eight minutes as an indicator of your VO2 max running pace. 

If you are doing a HIIT workout that is at 95% of your VO2 max, this would roughly equate to a running pace you could hold for 15 minutes of all-out running.

Interval sessions for improving VO2 max should have intervals that take between three and six minutes for each of the reps.

Improving aerobic capacity will help you have a more efficient cardiovascular system for half marathon and marathon distance running, which can help you use oxygen more efficiently at faster running speeds. 

This can improve your running economy and overall running performance for long distance races.3Barnes, K. R., & Kilding, A. E. (2014). Strategies to Improve Running Economy. Sports Medicine45(1), 37–56. https://doi.org/10.1007/s40279-014-0246-y

‌If the goal is to build speed endurance, you can run the repetitions at a slower pace, such as half marathon pace, and then take a shorter recovery jog in between each rep.

A person running fast on the road.

#3: Short Reps

It can also be helpful to do speed workouts with shorter reps at mile pace or faster to train your anaerobic system.

A classic speed training workout for distance runners from the 5k to the half marathon or marathon includes 8 to 12 reps of 400m at mile race pace or 5 to 10 seconds faster than 5k pace. 

#4: Fartlek Workouts and Road Running Speed Work

Aside from interval training on the track for marathon training programs, you can also incorporate fartlek workouts and tempo runs or threshold intervals on the roads or trails.

As a Running Coach, I work with many marathon runners who feel anxiety running on the track for timed speed work.

High-intensity fartlek workouts (HIIT) and longer distance tempo runs can be a great way to reap the benefits of speed training without having to use the track. 

You can also simulate race conditions with hilly courses when you are doing tempo runs or lactate threshold interval sessions on the roads.

The lactate threshold occurs around 83-88% of your VO2 max, so your lactate threshold training pace would be the pace you are running at 83-88% of your VO2 max according to your lab results or roughly the pace you could hold at max effort for an hour of running. 

For most runners, the lactate threshold pace is about 15-20 seconds per mile (9-12 seconds per kilometer) slower than your 10k race pace, much faster than your half marathon pace.

Therefore, if you run a 45 minute 10k race, your tempo runs and threshold interval workouts should be run around 7:30-7:35 minutes per mile or about 4:39-4:42 minutes per kilometer.

A person running fast.

#5: Long Runs With Speed Work

The long run will help you gradually build up your cardiovascular, musculoskeletal, and mental endurance for the marathon distance.

For beginners, the long run should always be run at an easy pace, without worrying about hitting your goal marathon pace or running fast. You are just building time on your feet.

However, experienced runners can use the long run as an opportunity to add in some faster pace work.

I sometimes have experienced marathon runners add several miles at goal marathon pace in a long run, or throw in a few intervals at 5k pace or VO2 max pace.

Doing a long run with some high-intensity speed work can help break up the monotony of running and to help get used to running at your goal marathon pace when your legs are tired.

However, the long run is inherently very taxing for the body, even when you run at an easy pace.

Therefore, when you layer speed work into the long run, you are putting your body through a difficult training session.

This needs to be considered when you are planning your easy runs over the days following a race pace long run or other advanced long run workouts.

People warming up on a track.

#6: Sprint Training

Adding strides to the end of easy runs is also a good way to incorporate some short, HIIT workouts and faster running without having to do full interval sessions, which are much more taxing for the body and mind.

Strides are essentially accelerations or sprints, so they help you work on your turnover and can help you improve your speed without needing significant recovery or rest days following this type of sprint training workout.4Koral, J., Oranchuk, D. J., Herrera, R., & Millet, G. Y. (2017). Six Sessions of Sprint Interval Training improves running performance in trained athletes. Journal of Strength and Conditioning Research32(3), 1. https://doi.org/10.1519/jsc.0000000000002286

‌In addition to these dedicated speed workouts, you should be doing easy runs to build your base and recover from the harder training runs, and you should have one long run per week.

Cross-training and strength training are also essential components for helping you reduce the risk of injuries and run faster.

Overall, interval training is a type of training that can benefit first time marathon runners all the way up to experienced runners and Olympic marathon runners.

Make sure to always do a thorough warm up and cool down after any type of speed training.

As your fitness level improves, you can incorporate shorter distances in your speed sessions at a faster pace combined with longer intervals at lactate threshold or half marathon pace to prepare you for race day.

Check out our marathon training plans for all levels here!

People high-fiving at the end of a track session.


Photo of author
Amber Sayer is a Fitness, Nutrition, and Wellness Writer and Editor, as well as a NASM-Certified Nutrition Coach and UESCA-certified running, endurance nutrition, and triathlon coach. She holds two Masters Degrees—one in Exercise Science and one in Prosthetics and Orthotics. As a Certified Personal Trainer and running coach for 12 years, Amber enjoys staying active and helping others do so as well. In her free time, she likes running, cycling, cooking, and tackling any type of puzzle.

6 thoughts on “Marathon Interval Training: How To Add It To Your Marathon Prep”

  1. I have joined my local club who run speed sessions… this takes the effort of planning out of the equation and my commitment is to just turn up. They mix it up with some weeks being sets of 200 and some at 400 or 600 but they are usually totally about 3.5-4K ( with the option to not do so many sets on the way out for the less fit/newby’s). I have found my weekly tempo runs and longer runs are getting easier at the tempo pace… I guess my body is adapting for the better! Roll on Athens marathon!

  2. Hi there, I’m confused after reading this article and this other one (https://marathonhandbook.com/yasso-800s/)
    Do you recommend Yasso 800’s alike intervals but your colleague does not? I am targeting a sub-3h marathon and I usually do 800m intervals in my anaerobic zone but now I am unsure if I should do longer (1200m-1600m) intervals at threshold zone, or a little of both short and long intervals. My Tempo runs are already done at steady and near threshold paces from 30-75min. I’d appreciate any insights you could give, I enjoy your content very much. Thank you!


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