european college of sport science

Saturday, June 27th, 2009
activity daily. This study represents a first survey which provides nation-wide representative data for physical activity and sports in Germany.
Methods: The target population of the study are all children and adolescents living and registered in the Federal Republic Germany aged
between 4 and 17 years. The participants of the study were recruited in 167 sample points across Germany. The sample consists of 4529
children and adolescents who were tested in regard to physical activity, motor fitness, and health status. The measurement of the compliance
with the activity guidelines was con-ducted on the basis of the screening questionnaire by Prochaska, Sallis and Long (2001).
Results and Discussion: Looking at the whole sample, only 15.3% of children and adolescents aged between 4 and 17 years meet the 60min
guideline. The proportion of girls (13.1%) meeting this guideline is significantly (chi2 = 14.0; df = 1; p < .001) lower than the proportion
of boys (17.4%). Fur-thermore, the results of this study lead to the conclusion that the proportion of children and adolescents who meet the
physical activity guidelines decreases with increasing age. Every third child of kindergarten age can achieve this activity guideline, however
in primary school the compliance with the activity guidelines is reduced to only every fifth child. With the transition to the secondary
school, there are less than 10% of adolescents meeting the 60-min guideline. Finally, in the age group between 14 and 17 years every
20th girl and every 12th boy comply with the activity guideline. These results suggest that only a small percentage of German children
and adolescents are sufficiently physically active und em-phasise the importance of endeavours to promote physical activity and sports
among chil-dren and adolescents.
Reference
Strong, W.B., Malina, R.M., Blimkie, C.J., Daniels, S.R., Dishman, R.K., Gutin, B. et al. (2005). Evidence based physical activity for school-age
youth. Journal of pediatrics, 146, 732–737.
European Commission (2008). EU Physical Activity Guidelines. Recommended Policy Actions in Support of Health-Enhancing Physical
Activity. Brussels: European Commission.
MUSCULAR STRAIN RISK FACTORS IN YOUNG SOCCER PLAYERS
VENTURELLI, M., SCHENA, F., BISHOP, D.
UNIVERSITY OF VERONA
Introduction: Soccer is a popular game practiced all around the world by teenagers. However, despite being a relatively safe sport,
muscle strain injuries during competitive matches are very common compared to other team-sports. Several studies have previously
reported potential intrinsic and extrinsic risk factors for soccer players. These include exposure time to training and matches, increased
age, previous injury, joint laxity, lack of training, and low endurance (Arnason 2004). While this information is valuable, few studies, to
date, have investigated risk factors for soccer injuries using Cox regression, as recommended by UEFA (Hagglund 2005). The specific
advantage of this advanced statistical is that it can be adjusted for actual playing time, which can vary greatly between players in the
same team. The aim of this study was to investigate the survivor covariates probability to muscle strains, in young soccer players.
Methods: 75 young soccer players (16.4±1.6 y) were followed for a season (10 months). At baseline, all players were tested for body size e
composition; yo-yo endurance test, flexibility, and jump performance (SJ, CMJ and DiHJ=CMJ-SJ). Team coaches and physicians recorded
players’ exposure (training and matches) and muscle thigh injuries (grade II lesions confirmed by echographic exam). A multivariate
stepwise forward Cox proportional hazards model was used to evaluate survival probability predictors, for thigh muscle strains.
Results: Significant correlations were recorded between thigh strain survival probability and: previous injury, field positions (defenders as
midfields), height, body mass, BMI, percent body fat, yo-yo step result, SJ and DiHJ. However, the multivariate Cox regression result (Haz.
Ratio; C.I. 95%) showed that, only previous injuries 2.74 (1.17-6.40), DiHJ 0.79 (0.72-0.88), and height 1.15 (1.05-1.25) were significantly
correlated to thigh strain survival probability.
Conclusion: This study confirms that previous injuries are an important risk factor, as reported by other investigations (Arnason 2004).
However, we also found that low jump ability and an elevated players stature increased the probability of a grade II thigh strain. This
could be explained by poor player coordination, influencing jumping ability (Bobbert 2001), which may be even more evident in tall young
players. An early evaluation, and regular monitoring, of these parameters could assist teams to identify players at high risk who needs to
be placed in preventative training programs.
References
Arnason A, et al. Risk factors for injuries in football. Am J Sports Med. 2004.
Hagglund, M. et al. Methods for epidemiological study of injuries to professional football players: developing the UEFA model. Br J Sport
Med. 2005.
Bobbert, M. Dependence of human squat jump performance on the series elastic compliance of the triceps surae: a simulation study. J
Exp Biol. 2001.
08:30 - 10:00
Oral presentations
OP-PH06 Physiology 6
PROTECTIVE EFFECTS CONFERRED BY FOUR BOUTS OF SUBMAXIMAL ECCENTRIC EXERCISE IN COMPARISON TO ONE
BOUT OF MAXIMAL ECCENTRIC EXERCISE
CHEN, T.C., CHEN, H.L., LIN, M.J., WU, C.J., NOSAKA, K.
NATIONAL CHIAYI UNIVERSITY
Introduction: A bout of eccentric exercise (ECC) confers protective effects against subsequent bout of more demanding ECC. Our recent
study (1) showed that a submaximal ECC bout, in which 30 lengthening contractions with a load of 40% maximal isometric strength (MVC)
were performed (40% ECC), conferred 20-60% protection against a subsequent bout of maximal ECC performed 2 weeks later. However,
its magnitude of the protective effect was significantly less than that (65-100%) conferred by the maximal ECC. It is possible that repeating
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