Organisation of instep kicking in young U11 to U20 soccer players

ABSTRACT

Aim: The main purpose of the study was to investigate kicking kinematics and performance in young-trained soccer players according to age, playing status, and biological maturity.Methods: Youth male soccer players (N = 105) from five age groups (under-11, under-13, under-15, under-17, and under-20) were evaluated. Four digital video cameras (300 Hz) captured the participants’ lower extremity and ball kinematics during penalty kick trials using dominant limb.Results: It was possible to identify non-linear differences in angular joint kinematics (displacement and velocity) of hip, knee and ankle across age-groups. Kicked ball speed and lower extremity mechanical factors discriminated among under-15 players with distinct status (e.g., ball speed and foot-to-ball speed ratio: starters > non-starters and non-participating substitutes; effect size = 1.05 to 1.49 [large]). Estimated maturity offset was not correlated with performance outputs in any age-group (r = −0.28 to 0.39; P > 0.05).Conclusion: We conclude that from ages ~10 to 19 years, differences in kicking kinematics and performance vary across time in youth players. Transition phase between under-13 to under-15 appears the most sensible period for powerful instep kick performance development. Kicking speed in youth soccer is discriminated according to player status, but not estimated biological maturity.

KEYWORDS:

• 3-D kinematics
• technique
• coordination
• development
• association football

Acknowledgements

The authors would like to thank all the players from Botafogo Football Club, John K. De Witt (NASA Johnson Space Center, USA) for his edits and very helpful comments and Klebert Palucci for the technical support provided.

Disclosure statement

No potential conflict of interest was reported by the authors.

Ethical statement

All procedures were approved by the Human Research Ethics Committee (University of São Paulo), under protocol number 1,108,137/2015, in agreement with resolution 466/2012 (National Health Council, Brazil) and the Declaration of Helsinki.

Data availability

Data underlying the findings presented here are provided as Supplementary online materials.

Additional information

Funding

This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001; São Paulo Research Foundation (FAPESP) under process [2016/50250-1], [2017/20945-0] and [2018/02965-7] and National Council for Scientific and Technological Development (CNPq) grants[472755/2008-0], [481833/2013-7] and [160963/2015-0].