There are many training plans and methods for running. The most common, and the one that is used as a foundation to influence many of them, is the 80/20 running method. You may already be doing it without realising. But what is it? And if you’re not already using it, how can you incorporate it into your running?

Whether you’re a marathoner or a beginner runner looking to get started with something more structured, understanding and implementing the 80-20 method could be the key to unlocking your full potential.

What is 80/20 running?

The 80/20 running method is rooted in the idea of balancing the distribution of training intensities. By doing this, we should experience better performance. The method advocates spending 80% of training time at low-intensity levels. You dedicate the remaining 20% to high-intensity efforts. Both running coaches and exercise scientists believe that this balance offers the perfect blend of volume and intensity for physiological adaptations without overtraining.

This ratio may seem counterintuitive. Many runners believe that pushing themselves to the limit during as many workouts as possible is the key to improvement. However, the 80-20 method challenges this idea, by emphasising the importance of balance and recovery.

The idea was first discovered in the early 2000s by Dr Stephen Seiler, an exercise physiologist. According to Seiler, the single most beneficial thing you can do to improve your performance in endurance running is to train a lot. There’s a caveat to that though. You need to make sure you don’t train too much, and risk overtraining. You do this by increasing your running volume at low intensities.

The science of 80/20 running

The main reason why scientists and coaches believe the 80/20 method works is because of the body’s physiological response to different training intensities. Low-intensity running enhances our aerobic capacity, improves endurance, and strengthens the cardiovascular system. On the other hand, high-intensity efforts, such as interval training and tempo runs, target our anaerobic capabilities and our ability to run faster.

Paula Radcliffe followed an 80/20 split in her training at her peak in 2003. For her, this looked like 12 of her 15 runs across 8 days being run at a low intensity. This meant she was running up to 160 miles per week.

That is an awful lot of volume and mileage for someone who is new to running or looking to improve their current pace or run longer distances. However, Dr Seiler did some research into whether the 80/20 split would still work for us mere mortals running more like 20 miles a week. The good news is, he found that it would!

In a study of recreational runners, sports scientist Jonathan Esteve-Lanao had a group of runners, who were running 30 miles a week. He split their training 50/50 between high intensity and low intensity. A second group followed an 80/20 split. The 80/20 group ran a faster 10K by 5% compared with a 3.5% improvement for the 50/50 group.

What is low intensity running?

It is common for people to run all of their runs as hard as possible. This works for some of us, to a point. Then, we tend to see the improvements plateau. This is because we’re getting too tired to do the higher intensity work as best as we can. The 80/20 method teaches us to hold back a bit on 80% of our runs to be able to give the 20% of high-intensity work our all.

It’s worth noting that what might be a low-intensity effort for one runner could be a high-intensity effort for another. Don’t be tempted to compare your pace, heart rate data or rate of perceived effort (RPE).

Long runs put additional stresses on our bodies because of the amount of time we’re running. That being said, they fall into the low-intensity category. They enable you to build endurance without excessive strain.

How to calculate your easy run pace

A running watch

Pace, measured in minutes per mile or minutes per kilometre, is easy to track using a running watch. It’s simple to follow when it comes to measurements. The slower the pace, the easier the run. There is a slight problem in using this metric to measure low-intensity running though, as there are several factors that can affect your pace. Running in the heat will make your pace on a cooler day feel tougher. Hill training will also slow your pace down if the route you’re running is lumpy. It may even be that you haven’t slept well the night before your run, and therefore your easy run pace may feel harder.

Heart rate

Heart rate is another metric that you can use for measuring your low-intensity runs. For low-intensity running, you should focus on keeping your heart rate in Zone 2. Zone 2 is exercise that is done at an intensity that is below your aerobic threshold, which is the point at which your blood lactate begins to increase. It is roughly 60-70% of your maximum heart rate. You’ll need to find out what range of beats per minute your personal Zone 2 is. There are a number of ways to do that, which start with finding your maximum heart rate.

There are several ways to calculate this. You can estimate your maximum heart rate based on your age by subtracting your age from 220. For example, for a 40-year-old person, the estimated maximum age-related heart rate would be calculated as 220 – 40 years = 180 beats per minute (bpm). This isn’t the most reliable measure. Although this formula has been used in a lot of past literature, it has recently been superseded by a different formula:

MHR = 205 – (.5 x your age) (MHR is ‘maximum heart rate’)

So, if you’re 40 years old, using the second formula, your maximum heart rate would be 185 bpm: MHR = 205 – 20.

This method doesn’t account for your fitness level. This means that your actual maximum heart rate could be anywhere from 10 to 20 beats per minute higher or lower than using only your age as a predictor.

As with your pace, there are a number of external factors that can affect your heart rate on any given day. Extreme temperatures and illness are just two examples of this, so take the measurement with a pinch of salt.

RPE

The final method for measuring the intensity of your running is RPE. This is a scale you can use based on how you feel. It’s completely subjective and you pick a number based on how tired you felt during your run, how sweaty you got and how high your heart rate was.

There are two scales that are used in physical activity; the 0-10 RPE scale and the original Borg Scale of 6-20. For simplicity, we’ll take a look at the 0-10 scale. The table below is taken from 80/20 Endurance LLC, co-founded by Matt Fitzgerald and David Warden. Fitzgerald has written books on the 80/20 running method and the company also provides training plans based on it as well as a zone calculator tool on the website which helps you set your own personalised zones.

According to Fitzgerald and Warden, for low-intensity runs you want to be aiming around 3 or 4 out of 10 on the RPE scale. When you start pushing a bit harder into 5 out of 10 territory, this is when you enter what they call ‘Zone X’ or ‘The grey zone’.

What is ‘the grey zone’?

When Fitzgerald and Warden say ‘the grey zone’ they’re referring to training at moderate intensity for extended periods. It’s the kind of running that you do that isn’t quite easy and isn’t quite hard. In fact, it’s the sort of intensity of running that most runners, especially new ones, find themselves going out and running at naturally. The 80/20 method says that this zone is counterproductive, and leads to the runner feeling more tired and being more prone to injury.

80/20 Endurance LLC refers to this intensity of running as ‘Zone X’. This is because it represents the ‘moderate-intensity rut’ that most runners get stuck in without realising it.

What is high intensity running?

Now we’ve covered how to run 80% of your runs at a low intensity, let’s look at the kinds of sessions you can include in your training that will make up the other 20% of higher-intensity workouts.

Interval sessions

Interval sessions are when you run short bursts at a quicker pace, with walking or jogging recoveries in between. They boost speed and anaerobic capabilities.

One of the key things to remember when you’re doing an intervals session is to keep the same intensity for all of the repeats (also referred to as reps or repetitions). There’s no point in rushing off for the first few and absolutely blitzing them. You will likely find that you’ve crashed and burned and can’t actually complete the whole session, or that the final reps are much, much slower than the first.

In order to work out the pace you should be going at, check out the distance of each rep. You wouldn’t hold the same pace over one kilometre as you would over 400 metres. The more you do high intensity training, the more you’ll be able to recognise the pace that you need for the distance.

You should always do a thorough warm-up before undertaking these sessions. Running at speed puts a lot of strain on all of your muscles, including your heart. If you don’t warm up properly, you run the risk of getting injured.

Tempo runs

Tempo runs are where you maintain a comfortably hard pace, to improve lactate threshold and enhance overall running performance. Generally, most tempo runs wouldn’t be longer than an hour. For some people, the terms ‘tempo’ and ‘threshold’ are interchangeable. ‘Threshold’ refers to lactate, which is what builds up in your muscles as you run. When you run underneath your lactate threshold, your body clears that lactate out as it goes. Above it, and it can’t clear it fast enough. So running ‘at threshold’ is about finding the sweet spot where you are clearing lactate at the same rate as you are accumulating it.

Hill sessions

Hill sessions can be classed as a high-intensity workout, because they build power in almost every leg muscle you use for running. Even if you’re training for a race that doesn’t involve hills, hill training is incredibly beneficial to you if you want to get faster. Being speedier on the uphills and building strength and power will make you faster on the flat, after all.

Find a steep hill and run up it at a hard effort, then jog or walk back down for recovery. Repeat for several reps, depending on your level of fitness.

How can I benefit from 80/20 running?

For us here at WR, 80/20 running has been a bit of a revelation! There are so many benefits of the 80/20 method for your running training.

• Reduced risk of injury
  By prioritising low-intensity running, runners tend to reduce the risk of picking up injuries, such as stress fractures and shin splints, because of the lower impact on their bodies.
• Enhanced endurance
  By spending more time doing low-intensity training, runners are able to increase their aerobic capacity and muscular endurance. This is ideal if your aim is to run longer distances and for it to feel easier.
• Improved recovery
  Lower-intensity runs mean that your body can recover more quickly. You’ll experience less muscle soreness and fatigue.
• Sustainable long-term training
  The 80/20 method is a balanced approach to training. Because of the reduced risk of injury and overtraining, as well as increased recovery, it means that you’re able to stay consistent over the long term. The 80/20 approach also promotes more consistency in training, as it reduces the likelihood of burnout and makes it easier for you to stick to your training plan.
• Allows for strength training
  We all know how important it is to do regular strength training to reduce injury and look after our bones. We also all know how hard it is to fit in a trip the gym around all our runs every week. Running at a lower intensity means that we don’t need as much recovery the following day, allowing our bodies to handle things like strength training, yoga or mobility in-between run days.

How do I incorporate 80/20 running into my training?

To effectively apply the 80/20 method in training, runners need to take a look at what their current training looks like. It might be that you just need to make a few tweaks to what you’re already doing. Alternatively, if you’re starting from the beginning, find a training plan that includes 80% low-intensity runs and 20% harder workouts.

The main change that runners who are already out there training can make is to slow their easy and low-intensity runs right down. It’s so common for runners to run their easy runs too hard and then not reap the benefits of the 80/20 method.

It may even surprise you what pace your easy runs should be run at. To give you an idea of the easy and low-intensity run pace, let’s imagine you can run a 50-minute 10K. That’s a pace of 08:03 per mile, so your easy runs should be in a range of 9:50-10:25 per mile. Two minutes slower than your 10K pace!

Whether aiming for a personal best in a marathon or simply seeking to improve overall fitness, the 80/20 method is a valuable tool in every runner’s toolkit. Embrace the balance, and let the journey to peak performance begin!