Article

Investigations corresponding to the affected factors of the cross-correlation of
pair muscles are limited though muscle activation patterns of bilateral erector
spinae (ES) during trunk flexion-extension performance in standing have been
utilized as an indicator in the evaluation of low back pain condition. The
purpose of the study is to evaluate the effect of leg support on the
cross-correlation of bilateral ES, and to test if the average of bilateral ES
could weaken this effect. Twenty male university students volunteered for this
study. Each performed the trunk flexion-extension in three leg support conditions
randomly with the condition of single left leg support, double leg support and
single right leg support, respectively. Each condition included three trials of
trunk flexion-extension with the cycle of 5s flexion and 5s extension in
standing. Surface electromyography from the right ES muscle as well as from the
left one was recorded. The cross-correlation both in pair muscle of right-left ES
and in pair muscle of right-average of bilateral ES was calculated in the flexion
as well as extension period. A one-way ANOVA with repeated measures was used. The
results showed that leg support has some effect on cross-correlation of bilateral
ES, which causes the absolute value of phase lag to be significantly larger in
flexion period. It is suggested that this effect could be weakened by the average
of bilateral ES through significantly increasing the cross-correlation
coefficient, and decreasing the absolute value of phase lag.
CI - Crown Copyright (c) 2013. Published by Elsevier B.V. All rights reserved.

Langue : ANGLAIS