Abstract
Metabolic analysis systems require binary sex input, conflating biological sex with gender, limiting inclusivity. This study aimed to determine whether sex input altered metabolic or pulmonary variables during self-paced walking and running. Twenty adults completed two 5-min walking and running trials under both female (FC) and male (MC) input conditions in randomized order. Dependent t-tests determined differences between conditions; p-values < 0.05 were considered significant, and effect sizes were calculated. No significant within-participant differences were found between FC and MC for any variable. During walking, mean relative VO(2) (mL/kg/min) was 11.13 ± 2.73 (FC) and 10.81 ± 2.39 (MC), p = 0.08, R(2) = 0.93; mean energy expenditure (kcal) was 18.28 ± 4.74 (FC) and 17.86 ± 4.33 (MC), p = 0.12, R(2) = 0.94. During running, mean relative VO(2) was 28.80 ± 5.89 (FC) and 28.82 ± 6.06 (MC), p = 0.90, R(2) = 0.98; mean energy expenditure was 45.79 ± 13.08 (FC) and 45.55 ± 12.26 (MC), p = 0.99, R(2) = 0.98. Binary sex input in the TrueOne 2400 system did not affect variables, supporting inclusive sex and gender data collection to improve research ethics, accuracy, and representation of gender-diverse people without compromising integrity.