Reference values for estimated VO 2 max by two submaximal cycle tests: the Åstrand-test and the Ekblom-Bak test.

AIMS: Submaximal tests estimating VO2 max have inherent biases; hence, using VO2 max estimations from the same test is essential for reducing this bias. This study aimed to establish sex- and age-specific reference values for estimated VO2 max using the Åstrand-test (Å-test) and the Ekblom-Bak test (EB-test). We also assessed the effects of age, exercise level, and BMI on VO2 max estimations.

METHODS: We included men and women (20-69 years) from the Swedish working population participating in Health Profile Assessments between 2010 and 2020. Excluding those on heart rate-affecting medicines and smokers, n = 263,374 for the Å-test and n = 95,043 for the EB-test were included. VO2 max reference values were based on percentiles 10, 25, 40, 60, 75, and 90 for both sexes across 5-year age groups.

RESULTS: Estimated absolute and relative VO2 max were for men 3.11 L/min and 36.9 mL/min/kg using the Å-test, and 3.58 L/min and 42.4 mL/min/kg using the EB-test. For women, estimated absolute and relative VO2 max were 2.48 L/min and 36.6 mL/min/kg using the Å-test, and 2.41 L/min and 35.5 mL/min/kg using the EB-test. Higher age (negative), higher exercise level (positive), and higher BMI (negative) were associated with estimated VO2 max using both tests. However, explained variance by exercise on estimated VO2 max was low, 10% for the Å-test and 8% for the EB-test, and moderate for BMI, 23% and 29%.

CONCLUSION: We present reference values for estimated VO2 max from two submaximal cycle tests. Age, exercise, and BMI influenced estimated VO2 max. These references can be valuable in clinical evaluations using the same submaximal tests.