Method Modulates: Protocol Choices Shape Sex Differences in the Determination of Exercise intensity
Meixner B, Schaffarczyk M, Sperlich B (2026)
Publication Type: Journal article, Original article
Publication year: 2026
Journal
Article Number: ajpregu.00266.2025
DOI: 10.1152/ajpregu.00266.2025
Abstract
Rationale: Exercise intensity is often prescribed as a percentage of a “maximum” reference point. Both the choice of reference and the protocol to obtain it may bias apparent female–male differences in relative intensity.
Objective: To examine whether female–male differences in relative intensity expressed relative to a maximum reference (V̇O₂max or PPO) differ depending on the protocol used to determine it (ramp vs. step).
Methods: Fifty trained cyclists (30 males, 20 females, 31±8 years old, V̇O₂max 3866±840ml/min) completed a ramp‐incremental and a 3-min step test on a cycle ergometer. Thresholds were determined from fixed and individualized blood lactate concentrations and from ventilation. Relative intensity was expressed in relation to PPO and V̇O₂max derived from each protocol. Linear mixed-effects models with participant as random intercept tested the fixed effects of Sex, Protocol, and their interaction. Agreement between ramp- and step-derived V̇O₂max values was evaluated using Bland–Altman analysis.
Results:. For V̇O₂-based relative intensity, only protocol effects were small but significant (all p<0.01). For Power, Sex had a significant influence in the models with males displaying higher relative intensities in all lactate-based thresholds (all p≤0.02). Sex × Protocol interactions emerged for BLa2 and BLamin+0.5(both p<0.05), indicating that using step or ramp protocols as reference can alter the magnitude or direction of female–male differences.
Conclusions: Apparent sex differences in relative intensity depend on how “maximum” is defined and obtained. The same relative intensity does not ensure equivalent physiological strain across sexes.
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Germany (DE)How to cite
APA:
Meixner, B., Schaffarczyk, M., & Sperlich, B. (2026). Method Modulates: Protocol Choices Shape Sex Differences in the Determination of Exercise intensity. American Journal of Physiology-Regulatory Integrative and Comparative Physiology. https://doi.org/10.1152/ajpregu.00266.2025
MLA:
Meixner, Benedikt, Marcelle Schaffarczyk, and Billy Sperlich. "Method Modulates: Protocol Choices Shape Sex Differences in the Determination of Exercise intensity." American Journal of Physiology-Regulatory Integrative and Comparative Physiology (2026).
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