Relationship between isometric cervical extension strength based on a cervical extension machine and the cross-sectional area of neck muscles.
- VernacularTitle:サービカルエクステンションマシーンによる等尺性頚部伸展筋力と筋断面積との関係
- Author:
KAORU TSUYAMA
;
YOUSUKE YAMAMOTO
;
HIDEO FUJIMOTO
;
KOUICHI NAKAZATO
;
HITONE FUJISHIRO
;
HIROYUKI NAKAJIMA
- Publication Type:Journal Article
- Keywords:
isometric cervical extension strength;
cross-sectional area;
neck girth
- From:Japanese Journal of Physical Fitness and Sports Medicine
2000;49(1):193-201
- CountryJapan
- Language:Japanese
-
Abstract:
The purpose of this study was to examine the relationship between isometric cervical extension strength and the cross-sectional area (CSA) of neck extensor muscles in order to obtain fundamental data for conducting neck muscle training to prevent neck injuries. Subjects were 8 males belonging to the judo or American football club in N University. Isometric cervical extension strength was measured at eight positions (0°, 18°, 36°, 54°, 72°, 90°, 108°, maximum flexion) using a cervical extension machine (Medx Inc., USA) . A transaxial magnetic resonance imaging (MRI) image of neck muscles was obtained at the intervertebral disk between C4 and C5 (using an MRI machine made by Hitachi medical Corp., JAPAN) . The findings were as follows.
1. The correlation between isometric cervical extension strength at 36°, 54°and 72°in a neutral position (60.8±1.4°) and the CSA of neck extensor muscles were higher than at other degrees (0°, 18°, 90°, 108°, maximum flexion) . In particular, there was a significant linear relationship at 54° (slightly extended position) .
2. A significant linear relationship was observed between the neck girth and CSA of neck extensor muscles.
In conclusion, there was a closer relationship between isometric cervical extension strengths at certain angles in a neutral position and the CSA of neck extensor muscles. Therefore, it was shown that isometric cervical extension strengths at certain angles in a neutral position mainly represented the CSA of neck extensor muscles.
