Astrand Test (cycle ergometer): submaximal protocol and VO2max estimation

The Astrand-Rhyming test is one of the classic submaximal lab tests: instead of pushing the subject to exhaustion, you ask for a steady, moderate effort on a bike for 6 minutes, and from the steady-state heart rate you estimate VO2max using nomograms or equations. It's especially useful when a maximal test isn't advisable or isn't necessary.

What does this test measure?

It estimates VO2max from the relationship between workload (power in watts) and steady-state heart rate during a submaximal effort, assuming a linear relationship between the two that can be extrapolated up to theoretical max HR.

Equipment needed

• Calibrated cycle ergometer (with power/resistance control)
• Heart rate monitor
• Stopwatch
• Astrand-Rhyming nomogram or a calculator with the age-correction formula

Step-by-step protocol

1. Warm up for 2-3 minutes at low intensity to adjust the saddle and get familiar with the ergometer
2. Choose a constant submaximal load that puts heart rate between 120-170 bpm (as a rough guide: 50-100 W for less trained people, 100-150 W for trained people; adjust by sex and fitness level)
3. Maintain that load for 6 minutes, recording heart rate at minute 5 and 6
4. If the heart rate between minute 5 and 6 differs by more than 5 bpm, extend the test by 1-2 more minutes until steady state is reached
5. Using the workload and the steady-state average heart rate, consult the Astrand-Rhyming nomogram to get the estimated VO2max
6. Apply the age-correction factor (VO2max decreases with age; the nomogram assumes ~25 years old, so you need to multiply by a correction factor specific to the subject's actual age)

Common mistakes

• Choosing a load that's too low or too high (outside the 120-170 bpm range reduces the nomogram's accuracy)
• Not waiting for heart rate to reach steady state before taking the reading
• Forgetting to apply the age-correction factor, which overestimates VO2max in people over 25

How to interpret the result

Reference table of estimated VO2max (ml/kg/min) after age correction:

Age	Men - Low	Men - Average	Men - High	Women - Low	Women - Average	Women - High
20-29	< 38	38-48	> 48	< 32	32-41	> 41
30-39	< 35	35-45	> 45	< 30	30-38	> 38
40-49	< 32	32-42	> 42	< 27	27-35	> 35
50-59	< 28	28-38	> 38	< 24	24-32	> 32

Related tests

The Astrand test is a great option when a maximal test (like Cooper or an incremental test to exhaustion) isn't advisable or doesn't add extra value:

• Incremental treadmill test — a maximal alternative if greater precision is needed and the subject can reach exhaustion
• FTP test — for cyclists already training with a power meter who want a more sport-specific performance figure

Track the data with Movalytics

The Astrand test requires combining workload, steady-state heart rate, age, and sex to get a reliable result — exactly the kind of calculation worth automating. With Movalytics you enter the load, heart rate, and the subject's data, and the app saves the estimated VO2max in the athlete's profile for comparison with future assessments.

Frequently asked questions

Why is it "submaximal" and what's the advantage? Because it doesn't require pushing the subject to exhaustion, reducing risk and fatigue, making it useful for the general population, older adults, or early phases of a program. Is it as accurate as a maximal test with gas analysis? No, its margin of error is larger (roughly ±10-15%), but it's a reasonable alternative when a maximal test isn't feasible or isn't needed for the purpose of the assessment. Can it be done on a treadmill instead of a bike? The original protocol is designed for a cycle ergometer, although submaximal treadmill variants exist with similar principles (load-heart rate relationship and extrapolation to theoretical max HR).