European Journal of Applied Physiology

, Volume 110, Issue 6, pp 1251–1257 | Cite as

Sex differences in force steadiness in three positions of the forearm

  • Ruth E. Brown
  • Darl L. Edwards
  • Jennifer M. JakobiEmail author
Original Article


The purpose of this study was to examine force steadiness in three positions of the forearm in young men and women across a variety of force levels. Eight young men and eight young women performed three maximum voluntary contractions (MVCs) in the neutral, supinated, and pronated forearm positions. Viewing a target line on a computer screen, subjects performed submaximal isometric contractions relative to their own MVC at 2.5, 5, 10, 25, 50, and 75% in each of the three forearm positions. Force steadiness was determined as the coefficient of variation (standard deviation around the mean force). A repeated-measures three-way ANOVA was used to assess the differences in force steadiness between sex, position, and force level. Men were stronger than women in all three forearm positions. Overall, men were steadier than women across all force levels and forearm positions. The neutral and supinated positions were equally strong and steady, and the pronated position was the weakest and least steady position. The forearm was most steady between 25 and 75% MVC, and least steady at the lower force levels. When correlations were run between MVC and coefficient of variation at all force levels and all forearm positions, a strong negative relationship was found (r = −0.49). In conclusion, men were stronger, as well as steadier, than women. The neutral and supinated forearm positions were both stronger and steadier than the pronated position. Results suggest that one of the primary factors influencing sex differences in force steadiness is absolute strength.


Strength Sex differences Force steadiness Neutral Supinated Pronated 



Authors would like to thank Mr. Don Clark, lab technician at the University of Windsor, for all his technical assistance with this study. They would also like to thank the Natural Sciences and Engineering Research Council of Canada for their financial assistance with this research.

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Ruth E. Brown
    • 1
  • Darl L. Edwards
    • 2
  • Jennifer M. Jakobi
    • 1
    Email author
  1. 1.University of British Columbia OkanaganKelownaCanada
  2. 2.University of WindsorWindsorCanada

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