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Updated: Oct 26, 2025
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Skeletal Muscle Gender Dimorphism from Proteomics
Published on: December 14, 2011
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Sex Differences in Muscle Metaboreflex Activation after Static Handgrip Exercise
Jordan B Lee1, Karambir Notay1, Jeremy D Seed1
1Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, CANADA.
Medicine and Science in Sports and Exercise
|July 26, 2021
Summary
Differences in muscle strength, not sex, explain greater blood pressure responses to exercise in men. Adjusting for maximal voluntary contraction (MVC) eliminated sex disparities in blood pressure during static exercise and postexercise occlusion.
Area of Science:
- Exercise Physiology
- Cardiovascular Regulation
- Sex Differences in Physiology
Background:
- Men exhibit greater blood pressure (BP) responses to relative-intensity static exercise than women.
- This difference is hypothesized to stem from altered muscle metaboreflex activation.
- The precise cause—intrinsic sex differences in metabolite production versus variations in muscle strength and absolute load—remains unclear.
Purpose of the Study:
- To investigate whether intrinsic sex differences in metabolite production or differences in muscle strength and absolute load contribute to greater BP responses during static exercise in men.
- To determine the role of muscle strength and absolute load in mediating sex differences in exercise-induced BP responses.
Main Methods:
- 200 healthy young adults (109 women) underwent static handgrip exercise at 30% maximal voluntary contraction (MVC) and postexercise circulatory occlusion (PECO), with continuous BP and heart rate monitoring.
- Muscle sympathetic nerve activity (MSNA) was measured in a subset (n=39, 21 women) to calculate resting sympathetic transduction.
- Sex differences in BP responses were analyzed with and without statistical adjustment for MVC, using multivariate regression.
Main Results:
- Men showed significantly larger systolic BP responses during exercise and PECO compared to women.
- Statistical adjustment for MVC abolished these observed sex differences in BP responses.
- No significant sex differences were found in MSNA responses during exercise or PECO, nor in resting sympathetic transduction.
Conclusions:
- Differences in absolute contraction load, dictated by maximal voluntary contraction (MVC), significantly contribute to sex differences in BP responses during exercise and metaboreflex activation.
- The findings do not support an intrinsic sex effect as the primary driver of exercise BP differences between men and women.
- Muscle strength, rather than sex per se, is a key determinant of exercise-induced blood pressure regulation.
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