Methods of identifying high velocity growth in youth soccer players

QP Physiology

McKenna, Michael ; MacFarlane, Niall

University:University of Glasgow

Department:Institute of Neuroscience and Psychology

关键词: Maturation, soccer, young athletes, high velocity growth, growth rate;   

Others  :  http://theses.gla.ac.uk/2078/1/2010mckennamsc.pdf

来源: University of Glasgow

【 摘 要 】

Soccer has been played as a competitive sport for more than 100 years. Recently, however, physical preparation has become increasingly important for elite players. Now more than ever, many young players are being encouraged to train intensely from an early age in order to prepare them in the best possible way to cope with the demands of the game and to increase their chances of becoming a successful professional soccer player. Yet adolescence is a stage of development characterised by unprecedented physiological changes in the musculoskeletal, cardiorespiratory and reproductive systems of the body. This has raised concerns that perhaps the specific practice of increasingly early soccer involvement and a greater training volume could put youth elite soccer players at risk of injury, in particular overuse injuries and strength disorders, especially during the adolescence growth spurt. The primary aim of this study was to establish a method of identifying soccer players going through high velocity growth (HVG) based on their physical and functional data, and to assess the effect to which this period of rapid growth has on muscle function and performance. Twenty-four male youth soccer players from Rangers Football Club’s U-14’s, U-15’s and U-17’s Youth Academy squads (Glasgow, Scotland, UK) were tested at three separate stages throughout the course of a year. Height, seated height, weight, body mass index, skinfold thickness (4-sites) and growth rates were collected as well as functional data on speed, agility, power, strength, flexibility and isokinetic concentric and eccentric muscle strength. Players going through the adolescence growth spurt were identified as having a growth rate two standard deviations outwith the average for their chronological age group.The results revealed that at the time of the study six out of the twenty-four players were going through a period of adolescent growth. The physical data showed that these players were smaller, weighed less and had a lower percentage body fat and body mass index compared to those players not going through HVG. There was no difference when comparing seated to standing height ratios and there was no evidence of a ‘fattening up’ period prior to HVG. The functional data showed that HVG players tended to be slower over 10 and 20m, have poorer agility, flexibility, power and strength compared with their peers. These results proved not to be statistically significant and it seems that the most accurate method of identifying players going through the adolescent growth spurt is with the use of retrospective physical data and calculating growth rates over a period of time. The results of this study do provide normative data for coaches, trainers and clinicians working with youth soccer players.In conclusion, youth soccer players especially from the age of 13-16, are continually growing and maturing and during this phase muscle function and performance are compromised. Players going through the adolescent growth spurt may be more susceptible to injuries as immature musculoskeletal system is less able to cope with repetitive biomechanical stress involved in youth soccer training and this is demonstrated in the poorer results shown in the HVG group functional tests. The adolescent growth spurt varies considerably in timing, tempo and duration and so trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt. It is therefore essential in a professional sporting environment to continually carry out physical and functional testing on youth players in order to identify those who are going through the adolescent growth spurt and ensure they are closely monitored.