Heart Rate Zones for Runners

Endurance
Written By Australian Athletics

An evidence informed guide for running coaches to maximum heart rate formulas, the Karvonen method, threshold based zones and the messy reality behind a neat five colour chart.

The central coaching idea
Heart rate shows how the athlete is responding to the run. Use it alongside pace, perceived effort, breathing, terrain and conditions to understand the full training demand and make better coaching decisions.

Heart rate is attractive because it is accessible. Pace tells a coach what the runner produced. Heart rate adds information about the runner’s internal cardiovascular response. That can be genuinely useful.

The problem begins when a watch turns one signal into five apparently precise zones without showing the assumptions underneath. A typical calculation may move from age, to an estimated maximum heart rate, to a chosen percentage system, to a zone label, and finally to a training decision. Every step can add uncertainty.

This article helps coaches use the information without becoming overawed by the arithmetic. The numbers may be exact. The physiological boundaries usually are not.

Start here

The chain of estimation

Before prescribing a zone, identify how many assumptions sit between the athlete and the number on the screen.

1

Estimate HRmax

An age equation may miss an individual runner’s true maximum by roughly 10 beats per minute or more.

2

Choose a model

Percentage of maximum heart rate, heart rate reserve and threshold models answer different questions.

3

Name the zones

“Zone 2” can mean low intensity in one system and between thresholds in another.

4

Coach the session

Heat, hills, fatigue, device error and heart rate lag can change what the number means today.

Perfect arithmetic cannot rescue uncertain inputs. Treat calculated zones as working ranges to test against breathing, perceived effort, pace and athlete response.
Best individual anchor Measured VT1 and VT2, or carefully identified lactate thresholds

These are closer to the physiological boundaries coaches usually intend their zones to represent.

Practical alternative Heart rate reserve with credible running HRmax and consistent resting HR

The Karvonen method has a sound physiological basis, but it still estimates rather than measures thresholds.1

Rough starting point Age predicted HRmax plus breathing, talk test and RPE

Useful when little athlete data exist, provided the coach is explicit that the range is provisional.

Common mistake Assuming a percentage band is an individual threshold

Fixed percentages do not reliably place every runner in the same physiological intensity domain.3

Interactive calculator

Calculate, compare and question the result

Use the same athlete data across four models. The calculator deliberately shows the method and its limitations, not just the answer.

Athlete inputs

Use a credible peak from an appropriate maximal run, race or test, not a random optical sensor spike.
Used only by the Individual thresholds model.
Sets the boundary between Zones 1 and 2.
Sets the boundary between Zones 2 and 3.
Zone model

The calculator runs only in this page. It does not send or store athlete data.

Heart rate reserve zones

Individual HRmax entered
HRmax used190
Resting HR50
HR reserve140
Threshold testing guide

What counts as a reliable measurement?

A reliable result identifies a physiological transition during a progressive running test and reports the heart rate observed at that point. It is not simply a percentage of maximum heart rate.

First threshold (VT1 or LT1)

Breathing and lactate begin to rise above easy levels. This is commonly used as the upper boundary of easy, sustainable running.

Second threshold (VT2 or LT2)

Breathing becomes hard and lactate rises more rapidly. Effort above this transition can usually be sustained for much less time.

Important: VT and LT use different measurements and may not produce exactly the same number. Only enter heart rates from a credible threshold test. If you do not have tested values, leave the fields blank and choose another zone model.

Best option
Running CPET for VT1 and VT2

An accredited exercise physiologist or appropriately trained practitioner conducts an incremental treadmill test while a calibrated metabolic system measures breath-by-breath oxygen uptake, carbon dioxide output and ventilation. VT1 and VT2 are identified from multiple gas-exchange markers, with the corresponding heart rates taken from the test.

Best option
Staged blood-lactate test for LT1 and LT2

The runner completes progressively faster treadmill or track stages, usually several minutes long, while capillary blood samples and heart rate are collected at each stage. The report should name the method used to identify LT1 and LT2 because several accepted lactate-threshold definitions exist.

Useful guide
Structured field assessment

A supervised graded field test using a chest-strap heart-rate monitor, pace, RPE and a standardised talk test can help bracket intensity, especially the first threshold, and guide training. Treat the resulting heart rate as an estimate unless the protocol has been validated and administered by a suitably qualified practitioner.

Estimate only
Watch predictions, fixed percentages and a single hard run

Automatic wearable thresholds, age formulas, percentages of HRmax, conversational feel and race averages can be useful sense checks. They do not, on their own, count as measured VT1/LT1 or VT2/LT2 values for this calculator.

Before accepting a result, check that:

  • the test was performed while running, using a progressive and documented protocol;
  • heart rate came from ECG or a well-fitted chest strap rather than an isolated wrist-sensor reading;
  • the report states the threshold method and gives HR in bpm at each threshold;
  • the athlete was rested, healthy, normally hydrated and tested in reasonably controlled conditions; and
  • repeat tests use the same mode, protocol and similar preparation so changes are comparable.

What should I enter? Copy the reported HR at VT1 and VT2, or at LT1 and LT2. Keep the pair from the same test method; do not mix VT1 from one test with LT2 from another. If the report only gives pace, power or broad zones, ask the tester for the threshold heart rates.

Evidence: incremental treadmill gas-exchange testing in runners16; staged lactate testing and the importance of the stated analysis method17; and validation of the talk test as a practical intensity guide rather than a direct physiological measurement18.
Why methods disagree

The same label can produce a very different run

Percentage of HRmax ignores resting heart rate. Heart rate reserve uses both ends of the athlete’s range. Neither automatically identifies VT1 or VT2.

Age formula comparison

These are population equations, not competing ways to discover one runner’s true maximum. In 4,043 runners, common prediction models showed individual errors of roughly 9 to 10 beats per minute.4

What does “70 to 80%” mean?

This live comparison uses the athlete values entered above.

A five zone table divides a scale. A threshold test attempts to locate physiological transitions. Those are not the same task.
Language matters

Translate “Zone 2” before prescribing it

The phrase has become popular, but it is not portable between systems. Select a model to see what the number commonly means.

Zone label translator

Coach decision tools

Choose the method that fits the evidence you actually have

The best method is not the most sophisticated option in a menu. It is the best supported option for this athlete and this session.

What athlete data are available?

How useful is live heart rate here?

H

Heat and prolonged running

Heart rate can rise at the same pace as cardiovascular drift develops. Interpret the number as changing internal strain, not necessarily a sudden loss of fitness.9

↗

Hills, wind and pace changes

Heart rate responds after the workload changes. On rolling terrain, pace and heart rate may appear to disagree simply because one moves faster than the other.

D

Device quality

A well fitted chest strap is generally preferable when precise exercise heart rate matters. Wrist optical devices can be useful, but movement and rapid changes may reduce accuracy.8

R

Resting heart rate

Use several calm morning readings under similar conditions. A single hurried reading turns the “individualised” Karvonen calculation into rather expensive guesswork.

T

Talk test and RPE

Comfortable speech and perceived effort provide useful cross checks when a zone is uncertain or conditions shift.10

M

Medication and health

Generic HRmax and HRR percentages may be unsuitable when medication blunts or alters heart rate. Use qualified clinical or exercise guidance rather than reverse engineering the watch.13

Applied examples

Three cases a running coach will recognise

The purpose of each case is not to find a magic number. It is to show the coaching decision hidden behind the calculation.

Case 1

Same maximum, different reserve

Asha and Ben both have a running HRmax of 190 bpm. Asha’s resting HR is 48. Ben’s is 68.

70% of HRmaxBoth 133 bpm
Asha at 70% HRR147 bpm
Ben at 70% HRR153 bpm

The HRmax method treats them identically. HRR accounts for their different usable ranges, although it still does not prove where either runner’s VT1 sits.

Coach action: use HRR as a starting range, then check breathing, pace stability and the athlete’s description of effort.
Case 2

The formula misses the runner

A 40 year old runner has an age predicted HRmax of about 180 bpm, but repeatedly reaches a credible 192 bpm in hard races.

80% HRmax using 180144 bpm
80% HRmax using 192154 bpm
Difference10 bpm

A low predicted maximum shifts every percentage zone down. The calculator may be functioning perfectly while the prescription is wrong for the athlete.

Coach action: replace age prediction with credible athlete data, but review the recording for sensor spikes and event specific validity.
Case 3

The long run drifts upward

A runner holds the same pace but moves from 145 bpm early to 156 bpm after 75 minutes on a warm day.

PaceStable
Heart ratePlus 11 bpm
Possible influencesHeat, duration, hydration

The higher value may reflect increasing internal strain. It does not, by itself, diagnose poor aerobic fitness, dehydration or overtraining.

Coach action: use an effort ceiling when the session purpose is easy, and review the pattern across comparable runs rather than judging one trace in isolation.
Evidence explained

What the research supports, and what it does not

Open each section for the evidence informed reasoning behind the coaching recommendations.

Heart rate reserve is calculated as HRmax minus resting HR. The target is then resting HR plus a chosen percentage of that reserve. Research has shown that percentage of HRR corresponds more closely with percentage of oxygen uptake reserve than with percentage of maximal oxygen uptake.1

That gives the Karvonen method a reasonable basis for prescribing broad aerobic intensity. It also accounts for resting heart rate, so two runners with the same maximum are not automatically given the same target.

The limitation: a percentage of reserve is still a percentage rule. It does not locate an individual runner’s first or second threshold.

A large analysis of 863 exercise tests found substantial variation in the position of ventilatory threshold when expressed relative to oxygen uptake reserve and heart rate reserve.2 Reviews of exercise intensity prescription reach a similar conclusion: fixed percentages of maximum values do not reliably place all people in distinct physiological domains.3

This is why an “easy” percentage can sit below VT1 for one runner and nearer or above it for another. Fitness level, testing method and individual physiology all matter.

Coach implication: use generic bands as broad starting points. Avoid calling them measured aerobic or lactate thresholds unless they were actually measured.

In a study of 4,043 runners completing maximal exercise testing, common HRmax prediction models showed root mean square errors of roughly 9 to 10 beats per minute.4 A 2026 exploratory study of 4,375 endurance athletes also found wide individual disagreement between age equations and self reported field maximum values, although its field data were self reported and should not be treated as laboratory validation.5

Small average bias can be misleading. A formula may be accurate for the group overall because overestimates and underestimates cancel each other out, while still being notably wrong for an individual athlete.

Coach implication: a credible running specific maximum is preferable to age prediction. A laboratory peak is useful too, but protocol and athlete motivation can affect whether a true maximum is reached.

A 2026 study of 1,411 endurance trained runners reported mean heart rates of 85.1 ± 4.6% of HRpeak at VT1 and 93.5 ± 2.5% at VT2.6 These values are more runner specific than a generic adult exercise table.

However, the standard deviations and subgroup differences are the important part of the story. The cohort averages can provide a reference or sense check, but they are not a test result for the runner standing in front of the coach.

Coach implication: the calculator includes these values as a clearly labelled cohort reference, never as “your threshold zones”.

In a physiological three zone model, Zone 1 sits below the first threshold, Zone 2 sits between the first and second thresholds, and Zone 3 sits above the second threshold. In many consumer five zone systems, Zone 2 instead refers to a relatively easy aerobic percentage band.

A 2025 expert viewpoint highlighted the lack of a universally standardised definition for the popular phrase “Zone 2 training” and favoured defining it relative to the first threshold.11 There remains debate about terminology and the best practical marker, so coaches should state the system rather than assume shared meaning.

Coach implication: write “below VT1”, “between VT1 and VT2”, or include the exact model. A zone number without its model is only half an instruction.

During continuous or longer steady efforts, heart rate can help monitor internal intensity once the response has stabilised. During brief repetitions, heart rate and oxygen uptake lag behind the rapidly changing workload, so athletes can finish the repetition before heart rate meaningfully represents its intensity.12

During prolonged running, heat and cardiovascular drift can push heart rate upward at an unchanged pace.9 Device error, terrain, stress, illness and medication can add further variation.

Coach implication: prescribe the session with the best primary variable. Use heart rate as a ceiling or cross check for easy running, but use pace, time, mechanics and recovery for short or fast repetitions.
A simple coaching protocol

Five questions before using a heart rate zone

1
What is the session trying to develop?

Start with purpose, not the number the watch happens to offer.

2
Where did HRmax and the boundaries come from?

Separate measured, observed, estimated and assumed inputs.

3
Is live heart rate responsive enough for this session?

It is more informative in steady running than in short repetitions or sprint work.

4
What other information agrees or disagrees?

Check pace, breathing, talk test, RPE, mechanics, terrain and conditions.

5
Is this a pattern or one noisy reading?

Coach trends across comparable sessions rather than reacting to every beat.

Final thought

Heart rate zones are useful when they make coaching decisions clearer. They become less useful when the apparent precision of the result hides the uncertainty of the inputs.

For many recreational runners, a sensible HRR range combined with breathing, talk test and RPE is a practical place to begin. For advanced runners, individual thresholds, critical speed, race performance and well understood field responses provide stronger anchors.

The goal is not to choose between data and coaching judgement. It is to use data that improves judgement. The watch can count every beat. It still cannot attend the debrief.

Sources

Selected evidence and further reading

The reference list prioritises peer reviewed primary studies, reviews and runner specific evidence.

Each entry links to the source. Where a paper sits behind a paywall the link points to its abstract or record. Figures quoted in the article are taken from these papers, not recalled from memory.

  1. Swain DP, Leutholtz BC (1997). Heart rate reserve is equivalent to percentage oxygen uptake reserve, not percentage VO₂max. Medicine & Science in Sports & Exercise.
  2. Gaskill SE, Skinner JS, Quindry J (2023). Ventilatory threshold related to VO₂ reserve, heart rate reserve and rating of perceived exertion in a large varied sample. Medicine & Science in Sports & Exercise.
  3. Jamnick NA, Pettitt RW, Granata C, Pyne DB, Bishop DJ (2020). An examination and critique of current methods to determine exercise intensity. Sports Medicine.
  4. Kasiak PS et al. (2023). Validity of maximal heart rate prediction models among runners and cyclists. Journal of Clinical Medicine.
  5. Ausland Å, Kelemen B, Seiler S (2026). An exploratory study of maximal heart rate determination in endurance athletes: laboratory testing versus field based. Frontiers in Sports and Active Living.
  6. Esteve Lanao J et al. (2026). Towards accurate reference values for heart rate and oxygen consumption at ventilatory thresholds in endurance trained runners. Sports.
  7. Wolpern AE et al. (2015). Is a threshold based model a superior method to the relative percentage concept for establishing individual exercise intensity? BMC Sports Science, Medicine and Rehabilitation.
  8. Pasadyn SR et al. (2019). Accuracy of commercially available heart rate monitors in athletes: a prospective study. Cardiovascular Diagnosis and Therapy.
  9. Wingo JE (2012). Cardiovascular drift during heat stress: implications for exercise prescription. Exercise and Sport Sciences Reviews.
  10. Bok D et al. (2022). The Talk Test, Feeling Scale and rating of perceived exertion for exercise prescription and monitoring. International Journal of Environmental Research and Public Health.
  11. What Is “Zone 2 Training”? Experts’ viewpoint on definition, training methods and expected adaptations (2025). International Journal of Sports Physiology and Performance.
  12. Coates AM, Joyner MJ, Little JP, Jones AM, Gibala MJ (2023). A perspective on high intensity interval training for performance and health. Sports Medicine.
  13. Wonisch M et al. (2003). Influence of beta blocker use on percentage of target heart rate exercise prescription. European Journal of Cardiovascular Prevention & Rehabilitation.
  14. Nes BM et al. (2013). Age predicted maximal heart rate in healthy subjects: the HUNT Fitness Study. Scandinavian Journal of Medicine & Science in Sports.
  15. Tanaka H, Monahan KD, Seals DR (2001). Age predicted maximal heart rate revisited. Journal of the American College of Cardiology.
  16. Benítez-Muñoz JA et al. (2024). Differences in the ventilatory thresholds in treadmill according to training status in 971 males and 301 females. European Journal of Applied Physiology.
  17. Fernandes TL et al. (2016). Post-analysis methods for lactate threshold depend on training intensity and aerobic capacity in runners: an experimental laboratory study. São Paulo Medical Journal.
  18. Quinn TJ, Coons BA (2011). The Talk Test and its relationship with the ventilatory and lactate thresholds. Journal of Sports Sciences.

All links checked August 2026.

Scope and safety: This resource is for coach education and general training prescription. It is not medical advice or a screening tool. Athletes with symptoms, diagnosed cardiovascular conditions, relevant medicines, pregnancy related considerations or other clinical concerns should receive appropriately qualified guidance.
Australian Athletics https://coachathletics.com.au
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