Franks et al. (2002) did not find any anthropometric or physiological differences between international players (aged 14-16 years) who became professionals and the players who did not. However, Reilly et al. (2000) using a multivariate analysis of anthropometric, physiological, psychological and soccer specific characteristics, observed that elite footballers (aged 16) compared to their non-elite (aged 15) counterparts, were leaner, faster, had more aerobic power and better tolerance to fatigue, and performed better on psychological and anticipation tests. The most discriminating measures were sprint time, ego orientation, anticipation skills and especially agility
Viviani et al. (1993) observed differences in height, weight, body fat and the endomorphy and ectomorphy of a group of “experienced” soccer players compared to “beginners” aged 12-13.