By Ben Green
B.Sc (Hons) Exercise & Health
Level 4 Distance Coach IAAF

Know Your Aerobic Training Zones

VO2 Max, Steady, Threshold….what does it all mean?  Knowing your individual aerobic training zones is crucial to ensuring you maximise the adaptations you can achieve from each planned workout or training run as well as reducing your risk of burnout or injury.


Have you heard runners talk about the Tempo run they did today, or the VO2 Max session they did on Tuesday?  In simple terms, different aerobic training zones will stimulate your body in different ways to achieve different adaptations. Whilst training at a variety of different training zones is encouraged for all runners, depending on your specific running goals, different training zones should be targeted to enhance the adaptations that are specific to your running training and racing goals.

The Details

Your 5 aerobic zones can be used to prescribe workouts that will best stress the cardio-vascular (CV) and muscular (M) systems to the desired degree.  Below is a summary of all 5 aerobic training zones and their main purpose:

Zone 5 = VO2 Max 

  • Interval efforts (typically 1-3min) that require rest or slow active recovery
  • This is a pace where the body burns all of the available oxygen (O2) to fuel the aerobic system. It is important to remember that runners can go quicker than this pace, BUT if they do, it is due to anaerobic contribution.
  • An acidic environment is created in the blood and working muscles due to accumulation of hydrogen ions (H+), making the pace sustainable for short periods of time only.
  • Fatigue is caused by CV and anaerobic (H+) sources due to an unsustainable demand of O2
  • Read more in our blog HERE

Zone 4 = Threshold

  • The pace that aligns with your anaerobic threshold
  • Longer efforts (typically >5min with steady float recovery) or a continuous run less than 30min total.
  • This is a pace where the body is using ALMOST all of the available O2 to fuel the aerobic system, meaning there is O2 available to buffer the acidic H+ that are being produced in the working muscles. H+ will therefore be present in the blood and working muscles but importantly, they do not accumulate.
  • This zone is often called the “red line” as any increase in pace above threshold will result in H+ accumulation and therefore the pace may not be sustainable for the planned time period of the session.
  • Fatigue is caused by CV sources due to a high demand for O2
  • Read more in our blog HERE

Zone 3 = Tempo 

  • This is the pace that sits between your anaerobic and aerobic threshold
  • Long efforts (typically >8min) or continuous runs between 30-60min total
  • The body is producing acidic H+ but due to the moderate demand of O2 by the aerobic system, they can easily be buffered and therefore NOT accumulate in the blood or working muscles
  • A tempo run is the junction point where fatigue will come from both CV (moderate demand for O2) AND muscular (from the duration of the run) sources
  • Read more in our blog HERE

Zone 2 = Steady 

  • The pace that aligns with your aerobic threshold
  • At a steady pace, your body just starts to produce H+ but they are almost instantaneously buffered due to a low demand for O2 by the aerobic system
  • This is recommended to be the quickest pace you run for any continuous run (e.g. easy or weekly long runs)
  • As you do not go above your aerobic threshold, fatigue will be muscular (or nutritional if you go far enough)
  • Read more in our blog HERE

Zone 1 (Easy) 

  • The pace that sits below your aerobic threshold
  • This should be the slowest pace you should run for any continuous run (e.g. easy runs, recovery runs plus warm ups & cool downs)
  • As you are below your aerobic threshold, there will only be fatigue from muscular & nutritional sources if you go far enough
  • If you cannot sustain your easy run pace, it is a sign you should be resting to ensure you recover from the stress you are under
  • Read more in our blog HERE

To work out YOUR aerobic pace zones, check out our Pace Calculator HERE

To learn more about how to apply these aerobic training zones towards your running goals in the most effective way, our specialist coaching team are here to help!  Contact us

By Ben Green
B.Sc (Hons) Exercise & Health
Level 4 Distance Coach IAAF

Main cover photo by Runner’s Tribe – MTC Training session at Falls Creek featuring Brett Robinson 2016