This test and calculator are designed to help you understand your aerobic efficiency, which is crucial for long-duration activities such as trekking, trail running, and mountaineering. Aerobic efficiency refers to how well your body can sustain steady, low-intensity work over time without excessive cardiovascular strain. The test can be performed using running, biking, rowing, or any steady-state cardiovascular activity where pace or output can be kept consistent.
A treadmill, bike, rowing machine, or a safe and measurable outdoor route if running or cycling outdoors.
A heart rate monitor or smartwatch capable of recording heart rate.
A means to track time (usually integrated into your watch or device).
A means to track pace, speed, or power
Cycling / rowing: power, speed, or stroke rate.
Measure your resting heart rate first thing in the morning, while still in bed.
Take readings on at least 2–3 different days and use the average.
Ensure you are well rested and not under the influence of caffeine, stress, or illness.
Your resting heart rate is entered into the calculator and is used to provide additional context for your aerobic efficiency result.
Running, biking, or rowing are all acceptable
Choose the modality that best fits your training needs and physical condition.
You must be able to perform the test continuously for 60 minutes without interruption.
Perform a 15-minute warm-up at a very easy pace.
Heart rate should remain well below pressured breathing.
You should feel warm, settled, and rhythmical by the end of the warm-up.
After warming up, continue your chosen activity for 60 minutes at a steady, controlled pace.
Aim for a comfortable aerobic effort.
You should be able to speak in full sentences.
Breathing should remain controlled and calm.
This effort should sit in Zone 2 or just below your aerobic threshold.
Your pace, speed, or power output is the control for this test.
Once the test begins, keep your output as consistent as possible for the full 60 minutes.
Do not adjust pace or power in response to heart rate.
Heart rate is allowed to rise naturally.
If your pace, speed, or power drops off significantly or varies widely, the test should be repeated on another day.
Begin recording heart rate as soon as the 60-minute test starts.
For accuracy, use average heart rate values, not single readings.
Average heart rate from minutes 25–30.
Average heart rate from minutes 55–60.
Finish with a 10–15 minute cool-down at an easy pace.
After completing the test, enter the following into the calculator:
Your age
Your resting heart rate
Average heart rate from minutes 25–30
Average heart rate from minutes 55–60
Calculate your heart-rate drift
High (Advanced)
Moderate (Intermediate)
Low (Poor)
A detailed explanation of your result and what it means for your training is provided in your results email.
Modality Adaptations.
Running should be performed where you won’t need to slow down or stop.
A treadmill or flat track with no road crossings is ideal.
If running is not practical, the test may be performed on a bike, rowing machine, or similar equipment that allows consistent, measurable output.
Consistency of effort and output is essential for valid results.
Including your resting heart rate helps provide a more personalised picture of your aerobic fitness and supports more accurate training interpretation and zone planning.
High aerobic efficiency indicates a strong aerobic base.
Moderate efficiency suggests the base is developing.
Low efficiency indicates a need for more focused aerobic base training.
Use the result to guide training priorities rather than chasing intensity too early.
This test, combined with the calculator, provides a practical way to measure and understand aerobic efficiency for endurance-based activities.
Regular testing allows you to track changes over time and ensure your training is building the aerobic foundation required for long days on the trail or in the mountains.
