Body composition analysis as a health index in cyclists

BACKGROUND: We aimed to verify the reduction of Body Mineral Density (BMD) in a group formed by young cyclists and the short-term efficiency of a vitamin D oral supplementation. METHODS: We enrolled 32 soccer players (CA) and 24 cyclists (CI) of same age (soccer players 18,4±0,9 years, cyclists 19,9±1,1 years; p=NS) belonging to same team in order to obtain same kind of training. Athletes were subjected to an evaluation of body composition through antropometric measurements, bioelectrical impedance analysis (BIA) and dual-energy X-ray absorbtiometry (DXA). Once established the reduction of BMD, cyclists were also subjected to blood samplings for vitamin D and calcium concentration (T0). These blood exams were repeated after two months (T1) of Cholecalciferol supplementation (T2) and after three more moths (T2), while DXA control was performed after 6 months. RESULTS: Main differences between these two groups relate to bone health specifically in BMD (CA: 1,2±0,2 g/cm2, CI: 1,0±0,1g/cm2; p=0,001) and Z-score (CA: 0,4 ±1,3 DS, CI: -2,3±-0,7 DS; p=0,02). Serum vitamin D and calcium at first blood sampling (26,49±3,901 ng/mL and 8,89±0,421 mg/dL) are at the lower level of range of normality. At the end of supplementation vitamin D concentration is normal (32,5±3,9 ng/mL), while calcium is back in range of normality after five months from the beginning of supplementation (9,4±0,4 mg/dL), no differences were found in BMD (1,0±02 g/cm2) and Z-score (-2,2±-0,6 DS) after 6 months of intervention. CONCLUSIONS: Body compositions confirms a reduced bone health in cyclists. The supplementation shows efficiency raising serum vitam D and calcium levels. Mostly in young athletes, a first level approach could be based on nutrition and a weight-bearing physical activity. It is clear the necessity of paying attention at bone health in cyclists, especially in young age in order to avoid an impairment of bone mass peak which could lead to a bone frailty in adulthood.