Effects+of+soccer+Expertise

Vänttinen, T, M Blomqvist , P Luhtanen, and K Häkkinen ."Effects of age and soccer expertise on general tests of perceptual and motor performance among adolescent soccer players.." //Pub Med.gov//. National Center for Biotechnology Information, 11 June 2010. Web. 7 Sep. 2010. [].>   "The results suggested that general perceptual motor skills improved with age, the development of these skills was related to participants' blood testosterone concentration (especially between 12 and 14 years), and general perceptual motor skills improved with soccer expertise."