Affiliations: [a] Health Welfare Laboratory, Kibi International University, Takahashi City, Okayama, Japan | [b] Rehabilitation Center, Okayama Central Hokancho Hospital, Kohjin Healthcare Group, Okayama City, Okayama, Japan
Correspondence:
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Corresponding author: Masanobu Murao, Health and Welfare Research Center, Kibi International University, 8 Iga-machi, Takahashi City, Okayama 716-8508, Japan. Tel.: +81 866 22 9454; Fax: +81 866 22 9406; E-mail:[email protected]
Abstract: BACKGROUND: Lumbar Multifidus (LM) exercise is a treatment in
patients with low back pain. We designed a new exercise using device
``Core-Noodle'' (Copyright has been observed in Japan). OBJECTIVE: The purpose of this study was to record the
electromyographic (EMG) activity of the lumbar multifidus during a novel
exercise. METHODS: Twenty-one healthy young volunteers performed the LM
exercise using Core-Noodle in three conditions: no-weight (NW), 1 kg weight
(1W), 2 kg-weight (2W). This exercise was performed in supine with left
shoulder abduct 90 degrees and right shoulder flexed 90 degrees. EMG
activity was recorded from surface electrodes on the LM and the thoracic
part of the iliocostalis lumborum (ICLT), and normalized to values derived
from maximal isometric trials (%MVIC). In addition, the ratio of the LM
to ICLT (L/G ratio) was calculated to compare selectivity of LM activity.
One-way ANOVA and Bonferroni method were used to draw comparisons among the
three conditions. RESULTS: Muscle activation of LM was gradually increased in
proportion to the loading dose. L/G ratio increased by weight loading
significantly, but slightly decreased at 2W. CONCLUSIONS: The results suggest that characteristic EMG patterns
of LM ``selective contraction'' and ``adjustment of load'' are obtained
concurrently.
Keywords: Lumbar multifidus (LM), low back pain (LBP), electromyography (EMG)
