Background
The body composition and its variation in time can affect the performances of soccer players. The body composition measuring techniques are based on a quantitative approach founded on indirect estimations of fat mass and lean body mass. The BIVA allows us to directly see the athlete's body composition by means of impedance vector measuring (Z vector), irrespective of weigh and body hydration status. The BIVA can classify hydration and mass variations of the soft tissues and recent observations testify that the higher the soccer player’s level, the larger the quantity of soft tissue. The purpose of this study is to observe the season variations of the soft tissues, as an indirect estimation of the nutritional condition of Italian Serie A elite male soccer players.