CROSS-SECTIONAL AREA OF PSOAS MAJOR MUSCLE IN HIGH SCHOOL ATHLETES
- VernacularTitle:高校生スポーツ選手の競技種目別の大腰筋断面積
- Author:
YOSHIHIRO HOSHIKAWA
;
TOMOMI IIDA
;
MASATAKA MURAMATSU
;
AKIKO UCHIYAMA
;
YOSHIHARU NAKAJIMA
- Publication Type:Journal Article
- Keywords:
MRI;
muscularity;
allometry;
junior athlete;
gender difference
- From:Japanese Journal of Physical Fitness and Sports Medicine
2006;55(2):217-228
- CountryJapan
- Language:Japanese
-
Abstract:
The aim of the study was to measure the cross-sectional area of the psoas major muscle (P-ACSA) in high school athletes and to produce a P-ACSA index independent of body size using an allometric modeling approach to examine the differences in gender and sport specialization. The subjects were 254 female (16.8±0.8 yrs) and 540 male (16.9±0.8 yrs) high-level high school athletes from 17 different sports. Fat-free mass (FFM) was measured by the Bod Pod system (LMI) and P-ACSA was determined by magnetic resonance imaging at the center of the L4-L5 transverse level. Since the power function model fit the data better than a simple linear model in the correlation between FFM and P-ACSA, and the power exponent parameter was almost equal to the theoretically anticipated 2/3 in both genders, the P-ACSA per FFM2/3 as well as the absolute P-ACSA was calculated. Both of the absolute P-ACSA and P-ACSA per FFM2/3 were significantly different according to gender and the sport specialization. While volleyball and badminton players and canoeists showed smaller P-ACSA, in accordance with the previous studies on senior sprinters, high school sprinters also showed predominant development of P-ACSA regardless of gender. These results suggested that regular involvement in sprinting activity could affect the size of the psoas major muscle in high school athletes.
