If you’re a runner looking to take your performance to the next level, then interval training could be just what you need.
Interval training is a type of workout that involves alternating periods of high-intensity effort with periods of rest or low-intensity effort. This type of intense exercise is a proven method for improving cardiovascular fitness, building strength, and increasing speed.
In this post, I explain what interval training is, how it works, and why it’s such an effective tool for all runners, whether you’re new to running, training for your next 10k race, or are training for a marathon or ultramarathon. Plus, I’m also sharing my three favorite interval running workouts for you to try.
What are the benefits of interval training for runners?
Although interval training workouts (also referred to by some as ‘speedwork’) may well be the hardest running workout you do all week, it’s worth the additional effort of doing this high-intensity exercise for the training gains you’ll benefit from.
Here are the 4 main benefits of incorporating interval training exercises into your running schedule:
1. Doing interval workouts is time-efficient
Interval training is a time-efficient way to improve your fitness. With interval training, you can get a great workout in a shorter amount of time than you would with a traditional steady-state workout where you may do moderate-intensity continuous training.
This is because interval training is designed to challenge your body with short bursts of high-intensity exercise, followed by rest or low-intensity exercise. By pushing your body to work harder in these short bursts, you can achieve more in less time.
2. Interval running helps build your endurance
By working your body with high-intensity exercise, you can increase your VO2 max and train your muscles to use oxygen more efficiently. This means that you’ll be able to run farther and for longer periods of time without feeling fatigued.
On the subject of oxygen, I definitely suggest you read how to breathe while running, as that post provides tips on how to maximize your breathing efficiency, which will help fuel your body with oxygen (and effective expel CO2).
3. It can help you become a faster runner
By pushing your body to work at a higher intensity, you can improve your running economy and stride efficiency, which means you’ll be able to run faster without expending as much energy.
Interval training can also help you improve your stride turnover, cadence, and running form, which are key factors in running speed and reducing your chances of running injuries.
4. Running intervals can help you burn more calories
By pushing your body to work harder during high-intensity intervals, you’ll burn more calories during and after your workout, which is good to know if you’re running to lose weight.
In fact, studies have shown that interval training can increase your metabolic rate for up to 38 hours after your workout, which means you’ll continue to burn calories long after you’ve finished your run. This is sometimes referred to as the Afterburn Effect.
Is interval training the same as HIIT?
Interval training and HIIT (High-Intensity Interval Training) are often used interchangeably, but there are some differences between the two.
What is High-Intensity Interval Training (HIIT)?
HIIT is a specific type of interval training that involves short bursts of high-intensity exercise followed by even shorter periods of rest or low-intensity exercise.
HIIT workouts are typically shorter than traditional interval workouts, and they may also involve plyometric exercises and movements such as burpees, or jumping jacks.
So, while all HIIT workouts involve interval training, not all interval training is HIIT. Interval training can be modified and adjusted to suit different fitness levels and goals, while HIIT workouts are typically more structured and intense.
Both are effective methods for improving fitness, building endurance, and increasing speed, but HIIT is a more specific and intense form of interval training.
The different types of running interval training workouts
There are several different types of interval training workouts that runners can use to improve their fitness, build endurance, and increase speed.
Here are the 6 most popular types of interval training workouts for runners:
1. Speed intervals
Probably the most well-known form of running interval training, speed intervals are a type of interval training that involves running at a high intensity faster speed for short periods of time (typically between 30 seconds and 2 minutes) followed by rest or recovery periods.
Speed intervals can be performed on a track, treadmill or on the road, and are great for improving running speed and increasing cardiovascular fitness.
2. HIIT (High-Intensity Interval Training)
As mentioned earlier, HIIT is a specific type of interval training that involves short bursts of high-intensity exercise followed by short periods of rest.
In the running world, HIIT intervals are essentially the same as sprint interval training with a short recovery period in between the intense efforts.
A specific type of HIIT interval training you may have heard of is Tabata, which is a form of HIIT that involves 20 seconds of all-out effort followed by 10 seconds of rest. It’s a highly effective way to boost cardiovascular fitness.
3. Hill repeats (aka hill sprint interval training)
Hill repeats are a type of interval training that involves running up a steep hill at a high intensity, and then jogging or walking down to recover before running up the hill again.
This type of workout is great for building leg strength and improving running form, and is one of my personal favorite ways to incorporate interval training into a weekly running program, especially if you are training for a trail running race from any distance, including trail marathons and ultramarathons.
Uphill running is one of the hardest, but most effective ways to train.
It’s especially great for improving your trail running ability given that most trail running involves running up and down hills of varying gradients. To learn more about the benefits and how to run up hills properly, read our guide to uphill running.
4. Pyramid intervals
Pyramid intervals involve gradually increasing and decreasing the length and intensity of your intervals.
You can build pyramid intervals into your hill repeats and/or speed interval workouts, and many runners use this technique in their training plans as it’s a great way to build endurance and speed.
5. Fartlek training
Fartlek is a type of interval training that involves varying your pace throughout the workout, and, in case you’re wondering, fartlek training is a Swedish word that means “speed play.”
Fartlek workouts are generally unstructured and involve running at a fast pace for short but varying periods of time, followed by slower recovery periods.
Fartlek workouts are great for building endurance and improving running form in a less structured or rigid training framework than other types of interval training.
6. Tempo intervals
Tempo runs are a type of training that involves running at a steady, high intensity for a sustained period of time (typically 20 minutes or longer), at a pace that’s often referred to by runners and running coaches as your threshold running pace.
Tempo runs are great for building endurance and improving lactate threshold, which is the point at which your body begins to produce lactic acid.
Tempo intervals are essentially runs with longer intervals. I typically like to do tempo intervals of between 3 and 5 minutes at a time, with a similar interval of ‘easy’ running to recover in between each one.
When I’m training for longer races such as marathons or 50ks, I throw in some longer intervals of up to 10 minutes of threshold pace at a time, usually towards the end of a longer training run. This simulates doing that final intense push to finish a race as you close on on that finish line!
How long should your running intervals be?
The length of running intervals depends on your fitness level and goals. If you’re new to interval training, it’s important to start with shorter intervals and gradually increase the length and intensity of your workouts over time.
For runners looking to improve their speed and endurance, interval training workouts should be between 20-40 minutes in total, including both work and recovery periods.
Duration-based speed interval ratios
You can choose to run intervals based on covering a certain distance, or over a certain time.
My personal preference and recommendation to new runners in particular is to focus your interval training based on duration, with a work-to-recovery ratio of 1:2. This ratio will help you recover enough between efforts so that you’re able to complete the full 20-40 minute workout.
So, for example, if you run a 1 minute speed interval, you would then do a 2 minute recovery interval before attempting another speed interval.
For endurance runners, your speed intervals may be longer, from two to five minutes at a time, with a proportionately longer recovery interval in between.
You can change your work-to-recovery ratio to something closer to 1:1 (i.e. your high intensity interval is the same duration as your low intensity recovery interval) but be mindful that this makes for an intense session and you may need to pace your efforts to avoid getting overly tired before the end of your planned workout!
High-intensity interval duration
For runners focused on using high-intensity interval training to increase speed over a short distance or duration, these are normally run as sprint intervals with each speed interval being less than one minute long, and sometimes as short as 15 seconds of effort at a time.
Hill repeat duration
Although you can do hill repeats based on duration (e.g. run uphill for 2 minutes), it’s usually easiest to let the length and steepness of the hill’s gradient dictate how you plan your session, regardless of how long it actually takes to run up.
This is also a fun way to see if you’re getting faster at running uphill.
My favorite way to track my uphill running speed to see if I’m getting faster is to create the uphill running section as a segment in Strava, so all my runs up that hill in future get logged against my previous times for that segment and I can push myself to get to the top faster each time.
For tips to improve your efficiency and speed on the ascents, read our guide to running uphill.
Interval training program examples for runners
Here are a couple of example interval training workouts for runners, which you can do as sprint (speed) interval training or hill repeat intervals:
Interval Workout #1: Speed Intervals To Build Endurance
If you’re training for a half marathon or longer, these speed intervals, combined with a weekly tempo run, will have you on your way to increasing your base running pace.
- Warm up with an easy jog for 5 minutes, incorporating some dynamic stretching to warm up your muscles.
- Run for 2 minutes at a fast yet sustainable pace, then recover for 3 minutes with an easy jog.
- Repeat the fast and slow intervals 6x for a total of 30 minutes.
- Cool down with 10-15 minutes of easy running and some stretching.
Interval Workout #2: HIIT workout to build running speed
Although short intervals are great for every runner to do, this workout is perfect for you if you are short on time and want to build your speed over shorter distances, including ensuring you have the ability to go for that sprint finish to your next race’s finish line!
Tip: This HIIT workout is a great one to do on a treadmill (but also easy to do outdoors).
- Warm up with an easy jog for 5 minutes, incorporating some dynamic stretching to warm up your muscles.
- Run for 30 seconds at a high-intensity fast pace, then recover for 30 seconds with an easy jog.
- Repeat the fast and slow intervals 10x to 15x for a total of 10 to 15 minutes.
- Cool down with 10-15 minutes of easy running and some stretching.
Interval Workout #3: Hill repeat intervals to build leg strength
Hill repeats are a fantastic workout to help improve your running form, leg strength and all-important power in your glutes. Plus, you’ll feel badass after completing this hill rep session.
- Warm up with an easy jog for 5 minutes, incorporating some dynamic stretching to warm up your muscles.
- Find a steep hill to run up (and down).
- Run uphill until you reach the top of the hill (or if it’s a long hill and you want a shorter interval, a landmark part-way up) then recover as you run back downhill at an easy pace.
- Repeat the up and downhill efforts for a total of 20-40 minutes. Depending on the hill length this could be as few as 4x or as many as 20x!
- Cool down with 10-15 minutes of easy running and some stretching.
Final thoughts on running interval workouts
Always warm up properly before starting the workout, and cool down and stretch afterwards to prevent injury and aid recovery.
The immediate recovery period at the end of your training session should be active, such as jogging or walking, to help clear lactic acid and gradually reduce your heart rate.
Post-interval training recovery
As well as the time immediately after your interval workouts, think about your recovery more broadly. These are tough workouts so consider the following to help you recover quicker and reduce potential for running injuries:
- Have a protein shake to help repair muscles after your runs. These are are favorite plant-based protein powders for runners.
- Take an ice bath (read how ice baths for runners can be a good idea!)
- Ensure you’re getting good quality sleep – here’s some tips on how to sleep better
- Take on board plenty of anti-inflammatory foods and nutrients. These greens powder drinks can help give you a boost!
No matter which type of interval training workout you choose, it’s important to tailor the workout to your fitness level and goals.
Remember, interval training is just one part of a well-rounded training program. It’s important to also include steady-state running, strength training, and flexibility work into your weekly run training schedule to maximize your running performance and reduce the risk of injury.
For more tips on increasing your running speed, read our post on tips and techniques to help you run faster.
