Affiliations: [a] Department of Rehabilitation Medicine, Wakayama Medical University, Wakayama, Japan | [b] Department of Orthopedic Surgery, Kitade Hospital, Wakayama, Japan | [c] Department of Neurology, Wakayama Medical University, Wakayama, Japan | [d] Department of Rehabilitation, Kokura Rehabilitation Hospital, Fukuoka, Japan
Correspondence:
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Corresponding author: Yukihide Nishimura, Department of Rehabilitation Medicine, Wakayama Medical University, 811-1 Kimiidera Wakayama-shi, Wakayama 641-8509, Japan. Tel.: +81 73 441 0664; Fax: +81 73 446 6475; E-mail:yuki-n@wakayama-med.ac.jp
Abstract: BACKGROUND: The erector spinae is more resistant to
fatigue in adult women than men. However, no study has reported the sex
differences in back muscle fatigue in children. OBJECTIVE: The aim of this study was to evaluate the fatigability
of erector spinae in prepubertal children and adults, in both males and
females. METHODS: Fourteen prepubertal boys, 13 prepubertal girls, 14 adult
men, and 13 adult women performed the Sørensen back isometric endurance
test until exhaustion. The results of electromyographic (EMG) power spectral
analysis of erector spinae were compared between both age groups and sexes. RESULTS: The slopes of EMG power spectral median and mean power
frequency were significantly higher in males than in females, in both age
groups. Furthermore, the slopes were significantly lower in prepubertal
children than in adults, in both males and females. CONCLUSIONS: Our results showed major differences in the fatigue threshold
of the erector spinae between boys and girls and children and adults. The
muscle fatigued faster in prepubertal boys and adult men than in prepubertal
girls and adult women. In both sexes, a lower slope of EMG power spectrum
parameters of the erector spinae was noted during endurance test in
prepubertal children compared to adults.
