Reference values for estimated VO₂max by two submaximal cycle tests: the Åstrand-test and the Ekblom-Bak test

Area of Science:

• Cardiovascular Physiology
• Exercise Physiology
• Public Health

Background:

• Submaximal tests for estimating maximal oxygen uptake (VO","2max) have inherent biases.
• Utilizing VO", "2max estimations from the same test is crucial for minimizing bias in clinical assessments.

Purpose of the Study:

• To establish sex- and age-specific reference values for estimated VO", "2max using the Åstrand-test (Å-test) and the Ekblom-Bak test (EB-test).
• To assess the impact of age, exercise level, and body mass index (BMI) on VO", "2max estimations derived from these submaximal tests.

Main Methods:

• Inclusion of 263,374 men and women (20-69 years) for the Å-test and 95,043 for the EB-test from the Swedish working population.
• Exclusion of participants on heart rate-affecting medications and smokers.
• Calculation of VO", "2max reference values based on percentiles (10th, 25th, 40th, 60th, 75th, 90th) across 5-year age groups for both sexes.

Main Results:

• Reference values for estimated VO", "2max were established for men and women across different age groups and sexes for both tests.
• Higher age was negatively associated, while higher exercise level was positively associated with estimated VO", "2max.
• Higher BMI was negatively associated with estimated VO", "2max, with moderate explained variance (23% for Å-test, 29% for EB-test).

Conclusions:

• Reference values for estimated VO", "2max from the Åstrand-test and Ekblom-Bak test are presented.
• Age, exercise level, and BMI significantly influence estimated VO", "2max.
• These sex- and age-specific references are valuable for clinical evaluations employing these submaximal tests.