title: Relative Age, Maturation and Physical Biases on Position Allocation in Elite-Youth Soccer.
abstract: This study assessed the contribution of relative age, anthropometry, maturation, and physical fitness characteristics on soccer playing position (goalkeeper [GK], central-defender [CD], lateral-defender [LD], central-midfield [CM], lateral-midfielder [LM], and forward [FWD]) for 465 elite-youth players (U13-U18's). U13-14 CD were relatively older than LD and CM (likelysmall effects). CD and GK were generally taller and heavier (likelysmall tovery-likelymoderate effects) than other players at each developmental stage and were advanced maturers at U13-14 (very-likelysmall tolikelymoderate effects). GK had inferior agility (very-likelysmall tolikelymoderate effects), endurance (very-likelysmall tolikelymoderate effects), and sprint capacities (likelysmall-moderate effects) vs. outfield positions at U13-14, but deficits in anaerobic phenotypes were diminished in U15-16 and U17-18. Position specific fitness characteristics were distinguished at U15-16 (likelysmall) and U17-18 (likelymoderate), where LM were faster than their central counterparts. In summary, relative age, maturation and anthropometric characteristics appear to bias the allocation of players into key defensive roles from an early development stage, whereas position-specific physical attributes do not become apparent until the latter stages of talent development in outfield players. Given the inter-individual trajectories of physical development according to biological maturation, playing position allocation might be considered 'plastic' by selectors, until complete-maturity is achieved.
authors.affiliation: Sport, Health and Exercise Science, The University of Hull, Hull, United Kingdom of Great Britain and Northern Ireland.
authors.forename: Chris
authors.initials: C
authors.lastname: Towlson
authors.affiliation: Faculty of Health Sciences, The University of Sydney, Sydney, Australia.
authors.forename: Stephen
authors.initials: S
authors.lastname: Cobley
authors.affiliation: Sport and Physical Activity, Edgehill University, Ormskirk, United Kingdom of Great Britain and Northern Ireland.
authors.forename: Adrian Wayne
authors.initials: AW
authors.lastname: Midgley
authors.affiliation: Sport, Health and Exercise Science, The University of Hull, Hull, United Kingdom of Great Britain and Northern Ireland.
authors.forename: Andrew
authors.initials: A
authors.lastname: Garrett
authors.affiliation: Pro Football Support, Huddersfield, Yorkshire, United Kingdom.
authors.forename: Guy
authors.initials: G
authors.lastname: Parkin
authors.affiliation: School of Science and Health, Sport and Exercise Science, Western Sydney University, Penrith, Australia.
authors.forename: Ric
authors.initials: R
authors.lastname: Lovell
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000886:Anthropometry; D054874:Athletic Performance; D006801:Humans; D010809:Physical Fitness; D012916:Soccer