Characterization of skeletal parameters in a cohort of North Italian rugby players

BACKGROUND: Vitamin D deficiency is common in the general population and may impair skeletal muscle function. Very few data are available regarding this condition in professional athletes. AIM: To evaluate some skeletal parameters and in particular serum 25-hydroxyvitamin D status in professional rugby players during two different sunlight exposure times (October and early April) and to assess its impact on bone metabolism. MATERIALS AND METHODS: Twenty-one male healthy professional rugby players living in northern Italy at latitude of 44°55'N (age 24.6 ± 4.3 years; height 182.0 ± 0.05 cm; mass 96.3 ± 14.6 kg; BMI 28.9 ± 3.7 kg/m(2)) participated in this observational study. During 2012/2013 Italian rugby season, 25-hydroxyvitamin D, PTH and other related biochemical parameters were monitored. Dietary calcium intake and body composition by DXA were also evaluated. RESULTS: Significant changes were observed between October and April data for 25-hydroxyvitamin D concentration (22.8 ± 5.8 vs. 19.1 ± 5.3 ng/ml; p = 0.001) whereas serum PTH, calcium and phosphorus plasma levels did not change. They presented with an appropriate daily intake of calcium (1,304.8 ± 477.9 mg; max 1,939 mg; min 228 mg). CONCLUSIONS: Professional rugby athletes practicing a sport characterized by intense outdoor training and with good calcium intake are at higher risk of hypovitaminosis D that worsens significantly during times of low cutaneous vitamin D production. Further studies are warranted to evaluate whether an appropriate supplementation with cholecalciferol in professional athletes is needed.