Objectives To identify the intrinsic risk factors of non-contact strains in the hamstrings and quadriceps muscles of professional soccer players via a cohort prospective design. Methods A total of 100 professional soccer players (aged 19.4–27.8 years) from four professional teams underwent a composite musculoskeletal assessment at preseason. Intrinsic risk factors included dichotomies of asymmetries in muscle strength, flexibility, proprioception, anthropometry and knee joint stability, and of previous injuries. Muscle strains were prospectively monitored during the subsequent season using questionnaires. The data were analysed via binary logistic regression.Results Thirty-eight percent of the players sustained one or more lower-extremity muscle strains. Sixteen (42.1 %) and seven (18.4 %) of them were clinically diagnosed as having non-contact muscle strains at their hamstrings and quadriceps, respectively. Players with eccentric hamstring strength asymmetries (OR=3.88; 95% CI 1.13 to 13.23), functional leg length asymmetries (OR=3.80; 95% CI 1.08 to 13.33) and no previous hamstrings injuries (OR=0.15; 95% CI 0.029 to 0.79) were at greater risk of sustaining a hamstring muscle strain. Players with eccentric strength (OR=5.01; 95% CI 0.92 to 27.14) and flexibility asymmetries (OR=4.98; 95% CI 0.78 to 31.80) in their quadriceps as well as heavier (OR=10.70; 95% CI 0.73 to 156.37) and shorter players (OR=0.08; 95% CI 0.00 to 1.35) were at greater risk of sustaining a strain in this muscle group. Conclusions Professional soccer players with functional asymmetries possess a higher risk of sustaining hamstring strains. Previous injury seems not to constitute a risk factor. The systematic isokinetic evaluation of the lower extremities during the preseason period can provide therapists and trainers with valuable data regarding the predictive elements of non-contact hamstring strains in professional soccer players.

The purpose of this study was to identify, categorize, and analyze published process-product research on physical education teaching methods completed between1960 and 2009. A literature search utilizing electronic databases yielded 138 studies which met the criteria for inclusion in the analysis. Each study was analyzed to obtain information on (a) the decade the study was published, (b) the number of authors, (c) the publication outlet, (d) the type of class, (e) the sampling method, (f) the effect size, (g) the statistics used, and (h) the statistical assumptions. The results indicated that most studies were the result of collaboration efforts among researchers. Also, intact classes rather than randomization were the most common technique used for forming the experimental groups. In the majority of the studies, the selection of the sample was done by means of purposive sampling techniques. A large proportion of the studies used univariate statistics to complete the data analysis.  However, the majority of the papers reviewed did not report effect size values nor did they report fulfillment of certain statistical assumptions.  The major publication outlet for process-product research was the Journal of Teaching in Physical Education.

The aim of this study was to identify volleyball performance indicators that best discriminate between winning and losing teams in a set according to set final score differences. The data were collected from teams’ performances (N=350) in all sets played during the 2009 Men’s European Volleyball Championship in Turkey. Clusters analysisestablished three different groups of sets according to set final score difference: 2 points (ambivalent), 3-5 points (safe), >5 points (unbalanced). A 3x2 MANOVA (type of set x type of result) was then performed on 9 performance indicators reflecting % expressions of four basic skills of the game (serve, pass, attack, block). The analysis revealed significant multivariate differences in type of set, in type of results, and in their interaction. A follow-up Discriminant Analysis showed that effectiveness of attack is the most important performance indicator for all types of sets, far more for the ambivalent ones. The discriminant function correctly classified increasing % of cases with increase in score difference. Especially for ambivalent sets 67.3% were correctly classified, letting some space for further improving the critical performance indicators. The results suggest that training of a men’s volleyball teamshould emphasize more to improve offensive abilities.

The purpose of the present study was to assess the relative importance of selected performance indicators in modern top-level handball through the analysis of offensive actions in three consecutive men’s world championships (2005, 2007 and 2009). A total of 288 matches were examined, which included 29,439 throw attempts resulting in 16,240 goals. The results demonstrated the strong relationship between the six-meter and nine-meter offensive actions, as evidenced by their very high negative correlation coefficients in both the throw attempts and goals scored. The significant decrease of the throw attempts and goals scored from the six-meter position, evidenced in the 2007 and 2009 championships, is associated with the collateral significant increase of the nine-meter throws and goals. Interestingly, the nine-meter efficacy remained relatively constant throughout the three competition years, while the six-meter efficacy depicted a significant increase in competition years 2007 and 2009 compared to 2005, as a result of the appearance of highlyqualified top ranking players in the pivot position. The high performance efficiency of these players resulted in adaptive defensive tactics to prevent the ball from reaching this key position. The present findings provide valuable information to handball coaches, in the design of their strategic and tactical plans.