The association of lower trunk muscle strength with low back pain in elite lightweight judokas is dependent on lumber spine abnormalities¹

Article type: Research Article

Authors: Okada, Takashi^{a; *} | Iwai, Kazunori^b | Hakkaku, Takayoshi^a | Nakazato, Koichi^c

Affiliations: [a] Faculty of Sport Science, Nippon Sport Science University, Setagaya-ku, Tokyo, Japan | [b] Department of Athletics (Wrestling), Western University, London, Ontario, Canada | [c] Graduate School of Health and Sport Science, Nippon Sport Science University, Setagaya-ku, Tokyo, Japan

Correspondence: [*] Corresponding author: Takashi Okada, Faculty of Sport Science, Nippon Sport Science University, 7-1-1 Fukasawa, Setagaya-ku, Tokyo 158-8508, Japan. Tel./Fax: +81 3 5706 0821; E-mail: t-okada@nittai.ac.jp.

Note: [1] This article received a correction notice (Erratum) post publication with DOI 10.3233/IES-229001, available at \hrefhttp://doi.org/10.3233/IES229001http://doi.org/ 10.3233/IES-229001.

Abstract: BACKGROUND: Lumbar radiological abnormalities (LRA) and trunk muscle weakness are major causes of the low back pain (LBP). We reported that the prevalence of LRA was approximately 90% in middle- and heavyweight-judokas, independent to the occurrence of LBP. However, the trunk muscle weakness, especially the rotators, plays a key role in occurrence of LBP in heavyweight judokas. OBJECTIVE: To examine the trunk muscle strength (TMS) and LRA impact on LBP occurrence in lightweight judokas. METHOD: The strength of the trunk extensors, flexors, and rotators was measured in 32 lightweight male judokas. LBP and LRA were identified using a questionnaire, X-ray, and MRI. RESULTS: The occurrence rate of LBP and LRA were 40.6% and 62.5%, respectively, without any significant correlation. Among judokas without LRA, TMS of those with LBP were significantly lower than those without LBP (P< 0.05, the extensor; 60∘/s: ES [d] = 1.38, 90∘/s: ES [d] = 0.78, and 120∘/s: ES [d] = 0.37, flexor; 60∘/s: ES [d] =  1.48, dominant rotator; 60∘/s: ES [d] = 1.66, and 90∘/s: ES [d] = 1.87, non-dominant rotator; 90∘/s: ES [d] = 0.17, and dominant/non-dominant rotator ratio; 90∘/s: ES [d] = 1.55). Moreover, there were significant negative correlations between LBP severity and TMS (P< 0.05, the extensor; 90∘/s: r=-0.63, dominant rotator; 90∘/s: r=-0.648, and dominant/non-dominant rotator ratio; 90∘/s: r=-0.621) in judokas without LRA. CONCLUSION: Weak trunk musculature may be a co-factor in the occurrence of LBP in lightweight judokas without LRA.

Keywords: Martial art, weight category, injury, torso rotation, MRI, radiographs, X-rays

DOI: 10.3233/IES-210193

Journal: Isokinetics and Exercise Science, vol. 30, no. 2, pp. 177-186, 2022