Associations between serum 25 hydroxyvitamin D concentration and body composition of college male rugby players / 体力科学

ABSTRACT

This study aimed to clarify the relationship between serum 25-hydroxyvitamin D concentration body composition by examining male university rugby players in a cross-sectional manner. The subjects were 36 male rugby players (mean age 20.2 years) who provided us with data regarding their body composition, blood biochemistry examination, and dietary intake frequency. Examination of their serum concentrations of 25-hydroxyvitamin D 【25 (OH) D】 showed that 58% (21/36 subjects) and 42% (15/36 subjects) had sufficient and insufficient intake of vitamin D, respectively. In comparison of serum 25 (OH) D concentrations between players in individual positions, it was suggested that the concentrations were significantly lower in the forward (FW) players compared with the backs (BK) players (p<0.01). The number of FW players with lipid abnormality was significantly higher than that of BK players (p<0.01). Serum 25 (OH) D concentrations showed negative correlations with weight, Body Mass Index (BMI), total body fat amount, and lean body weight. Multiple linear regression analysis suggested that serum 25 (OH) D concentration would be affected by BMI. The average serum 25 (OH) D concentration among obese class II – IV players was 27.8 ng/mL, which was significantly lower than that of players with a normal weight or obese class I (34.2 ng/mL, p<0.01, 33.1 ng/mL, p<0.01). These findings suggest that vitamin D intake among obese class II – IV players was not sufficient, despite the fact that their intake of vitamin D was 14.1 µg, which was much higher than the adequate intake level. In the future, further studies should clarify how increased intake of vitamin D could improve physical characteristics.