Reference values for arm ergometry cardiopulmonary exercise testing (CPET) in healthy volunteers

The performance of a cardiopulmonary exercise test (CPET) requires an individual to undertake a progressive, maximal exercise test to a symptom-limited end point. CPET is commonly performed using a treadmill or cycle ergometer (CE). Arm ergometry (AE) is an alternative exercise modality to CE; however, AE produces lower peak oxygen uptake (V̇O₂) values as it involves smaller muscle groups and generates less cardiovascular stress. Current predicted equations for the interpretation of AE CPET are limited by small sample sizes, gender bias and limited age ranges.

To develop predicted equations and reference ranges for AE exercise testing.

Incremental ramp protocol CPET, to a symptom-limited end point, via AE was performed in a group of 116 (62 F) healthy volunteers of median age 38 (IQR 29-48) years. Breath-by-breath gas analysis was performed using the Ultima CPX (Medical Graphics, UK) metabolic cart. Quantile regression analysis was used to develop regression equations for AE V̇O₂, peak work rate (WR), anaerobic threshold, peak ventilation (VE), peak heart rate, oxygen pulse, V̇E/V̇CO₂ slope and V̇O₂/WR slope.

Reference equations including upper and/or lower limits, based on quantile regression, were generated and verified using a validation cohort.

These findings represent the largest and most diverse set of predicted values and reference ranges for AE CPET parameters in healthy individuals to date. Implementation of these reference equations will allow AE to be more widely adopted, enabling the performance and interpretation of CPET in a wider population.