Factors relating to gender specificity of unloading-induced declines in strength.
BACKGROUND
This investigation aimed to: (1) confirm whether women were more vulnerable to the negative neuromuscular adaptations elicited by muscle unloading and if so, (2) determine which physiological mechanism(s) explain those gender-related differences.


METHODS
Healthy young men (20.7 ± 0.3 years) and women (20.3 ± 0.3 years)-(N = 12/group)-participated by completing neuromuscular functional tests before and after 7 days of unloading.


RESULTS
During isokinetic testing of peak torque, work performed, and power, women displayed significantly (P ≤ 0.05) greater declines in performance than men at 1.05 and 2.09, but not 0.53 rads/s. During maximal isometric contractions, women experienced greater strength decrements. Similar gender-specific adaptations to unloading were found in EMG activity, but not muscle mass, neuromuscular transmission, or force relative to EMG.


CONCLUSIONS
Women are more susceptible to the adaptations of muscle unloading, and disturbances in neural drive from the central nervous system are probably responsible.
Department of Kinesiology & Health Sciences, The College of William & Mary, Williamsburg, Virginia 23187-8795, USA. mrdesc@wm.edu
Michael R
MR
Deschenes
Raymond W
RW
McCoy
Katherine A
KA
Mangis
D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D012737:Sex Factors; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult