B Van Renterghem

A multidisciplinary selection model for youth soccer: the Ghent Youth Soccer Project

Objectives: To determine the relationships between physical and performance characteristics and level of skill in youth soccer players aged 12–16 years. Methods: Anthropometry, maturity status, functional and sport-specific parameters were assessed in elite, sub-elite, and non-elite youth players in four age groups: U13 (n = 117), U14 (n = 136), U15 (n = 138) and U16 (n = 99). Results: Multivariate analyses of covariance by age group with maturity status as the covariate showed that elite players scored better than the non-elite players on strength, flexibility, speed, aerobic endurance, anaerobic capacity and several technical skills (p<0.05). Stepwise discriminant analyses showed that running speed and technical skills were the most important characteristics in U13 and U14 players, while cardiorespiratory endurance was more important in U15 and U16 players. The results suggest that discriminating characteristics change with competitive age levels. Conclusions: Characteristics that discriminate youth soccer players vary by age group. Talent identification models should thus be dynamic and provide opportunities for changing parameters in a long-term developmental context.

Antibiotic resistant sulphite-reducing clostridia in soil and groundwater as indicator of manuring practices

The use of tetracycline- or oleandomycin-resistant sulphite-reducing clostridia as indicators for the application of piggery manure or cow dung was investigated. Sulphite-reducing clostridia resistant to either tetracycline or oleandomycin were detected in all the investigated cattle and piggery manure samples. They were present at high concentrations in the soil of manured fields and virtually absent in the soil of unmanured fields. Antibiotic resistant sulphite-reducing clostridia were also detected in the soil at a depth of 100 cm and in the groundwater of manured fields while they were present at a much lower degree in the groundwater of unmanured fields. The numbers of faecal coliforms and faecal streptococci in groundwater samples were not clearly related to the application of piggery manure.