How fundamental endurance training can improve your running

Fundamental endurance (running at an easy pace) is an essential component of training. Running slowly will paradoxically help you improve greatly in the medium and long term.

Slow endurance running is the cornerstone of any training plan. It improves the cardiovascular system and prepares the body for incremental increases in the volume of training.

The benefits of fundamental endurance training

Among its benefits, fundamental endurance allows runners to:

  • increase cardiac output
  • lower resting heart rate and lower heart rate at each given effort
  • increase the number of capillaries (very small blood vessels) and mitochondria which leads to better oxygenation of the muscles
  • improve recovery

In the medium term, by doing lots of easy running, this teaches the body to transport oxygen to the muscle cells and use it more efficiently.

What pace is fundamental endurance?

Care must be taken not to exceed 70% of your maximum heart rate, generally around 130-140 beats per minute, if the measurement on your heart rate monitor is correct. In terms of speed, this corresponds to approximately 60-65% of your Maximum Aerobic Speed (MAS).

More simply, when running in your fundamental endurance zone, you should not be out of breath, and should be able to comfortably hold a conversation. If you start breathing too hard, you are no longer in fundamental endurance.

During these runs, the body favours lipids as the main energy supply. Whereas at faster paces, carbohydrates are more in demand to provide energy to the muscles.

For marathon runners, training at fundamental endurance can help delay the arrival of the marathon wall, that moment around the 35th kilometre where you feel a drop in speed.

However, runners sometimes find it difficult to stay in this effort zone, because the pace seems slow (around 10km/h for a runner with a MAS of 15km/h). It may feel uncomfortable to run this slowly.

But you will see after several weeks the body will learn to run at this rhythm. Gradually you will adapt and this will allow you to increase your pace a little whilst staying in the right heart rate zone.

To practice exercising with the heart rate at 70% of your maximum, you can also go biking, power walking, hiking, cross-country skiing and other sports.

For example, I have a MAS of 21km/h, and for fundamental endurance runs my pace is 12km/h. I like these paces because I feel easy and I feel like I recover well between sessions.

How much fundamental endurance should there be in a training plan?

At least 60-70% of your weekly mileage should be done at this pace.

How do you devote 60-70% of your weekly mileage to fundamental endurance pace?

  • During warm-up jogs before a session and warm-down jogs after the session
  • During recovery runs between sessions
  • During long runs

Fundamental endurance is around the pace of ultra-trail runners, races of more than 100km. It’s a pace you feel like you can hold for an almost unlimited amount of time. You might also go at this pace during hiking-running training, alternating walking and running depending on the technicality of the trail.

With a solid aerobic foundation through fundamental endurance training, you will also be able to develop your VO2max with interval sessions.

There is no need to do all your runs too fast. Fundamental endurance is essential for runners of all levels.

Within the RunMotion Coach app, training paces are automatically calculated based on your level and previous race results. Tens of thousands of runners are already using it to prepare for their next running goals, discover the RunMotion Coach app too.

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Jamie Taylor-Caldwell14.21 5000m runner and former scholar athlete for West Texas A&M. Jamie is the UK Country Manager for RunMotion Coach