<p>Calculation sheet.</p>

Study design Cross-sectional validity study. Objectives To determine the criterion validity, Standard Error of the Measurement (SEM) and Minimal Detectable Change (MDC), of a newly developed submaximal test (Holmlund-Grooten test) for estimating the peak oxygen consumption in wheelchair users with motor-complete Spinal Cord Injury (mcSCI). Settings Outpatient rehabilitation centre in Stockholm, Sweden. Methods Peak and submaximal oxygen uptake (VO2) was measured using indirect calorimetry. A backward linear regression model, including heart rate, power output, and several demographic variables, was used to predict absolute VO2peak. Results In total, 63 individuals (16 females) with mcSCI were included. The final prediction model included four significant (p < 0.05) variables (sex, injury level, heart rate, power output) that were able to predict absolute VO2peak (adjusted R2 = 0.77). The Holmlund-Grooten test showed excellent criterion validity (ICC = 0.88; 95%CI 0.83–0.94), SEM = 0.05 L·min-1 and MDC = 0.13 L·min-1. No adverse events were reported. We provide an Excel file that calculates VO2peak based on the Holmlund-Grooten model for males and females and tetra- and paraplegia for clinical use. Conclusion The Holmlund-Grooten test is a valid submaximal test for estimating VO₂peak in wheelchair users with SCI and can be easily implemented in clinical settings.