Title

Spinal Motor Control Differences between the Sexes

Document Type

Article

Language

eng

Format of Original

6 p.

Publication Date

3-2012

Publisher

Springer

Source Publication

European Journal of Applied Physiology

Source ISSN

1439-6319

Original Item ID

doi: 10.1007/s00421-012-2363-3

Abstract

Activity-related knee joint dysfunction is more prevalent in females than males. One explanation for the discrepancy is differences in movement patterns between the sexes. However, the underlying mechanisms responsible for these differences remain unidentified. This study tested spinal motor control mechanisms influencing motor neuron pool output and subsequent muscle activation in 17 males and 17 females. The following variables were assessed at the soleus: the gain of the unconditioned H-reflex, gain of both intrinsic pre-synaptic inhibition (IPI) and extrinsic presynaptic inhibition (EPI), the level of recurrent inhibition (RI), the level of supraspinal drive determined by the ratio of the Vmax:Mmax (V-wave), electromechanical delay (EMD) and the rate of force development (RFD). The Wilks Lambda multivariate test of overall differences among groups was significant (p = 0.031). Univariate betweensubjects tests revealed males had greater RI (p = 0.042). However, the sexes did not differ on any of the other variables tested. In conclusion, the sexes differ on modulation of spinal motor control. Specifically, RI, a post-synaptic regulator of force output, was greater in males.

Comments

European Journal of Applied Physiology, Vol. 112, No. 11 (March 2012): 3859-3864. DOI: 10.1007/s00421-012-2363-3.