Is an external focus of attention more beneficial than an internal focus to ball catching in children?

The performance benefits of adopting an external relative to an internal focus of attention have been demonstrated for many different targeting and balance tasks. No study has examined attentional focus effects for interceptive motor skills. Also, the majority of studies have used adult participants. In this study, children (mean age: 8.75 years, SD=0.79; 15 girls, 9 boys) were required to catch tennis balls in the frontal plane under the external focus (EF), internal focus (IF), and control (Cont) conditions. Participants were asked to stand behind a yellow line (2 × 100 cm), 15 m apart from a tennis ball throwing machine. In a within-participant design, participants performed 10 trials under each IF (“concentrate on your hands”), EF (“concentrate on the ball”), or Cont (no focus instructions) conditions. The order of conditions was counterbalanced. Performance data were analyzed using a one-way analysis of variance (ANOVA) with repeated measures on attentional focus conditions (internal, external, and control) (alpha=.05). Catching performance was significantly different and more effective in the EF (M=1.53, SD=0.25) than in the IF (M=1.39, SD=0.35) condition, while both EF and IF were not significantly different from the Cont (M=1.49, SD=0.28) condition. The current findings suggest that the external focus of attention is more beneficial, compared to the internal focus, to motor performance of an interceptive skill in children

Varijacije tijekom sezone u izokinetičkom vršnom momentu sile kod mladih nogometaša

The aim of the study was to investigate the seasonal variation in the strength of the knee flexors and extensors in highly trained youth soccer players. The players (n=16; age 16.7±0.7) were measured at the end of the competitive season, at the beginning of the off-season and during the sixth week of a new competitive season. Isokinetic concentric peak torque was measured at 60°•s-1, 180°•s-1, 360°•s-1 in a sitting position. The testing range of motion was set from 10–90° of knee flexion. Players performed a set of six maximal repetitions for both dominant and non-dominant limb. Average values of peak torque significantly changed during the observed periods. Significant differences (p<.05) between the three measurement sessions were noted with respect to the knee flexors at all angular velocities. A post-hoc test confirmed a significant increase between the first and the second measurement for flexion in both dominant (180°•s-1; p=.033) and non-dominant legs (360°•s-1; p=.004). A significant increase was also found between the first and the third session for both limbs during knee flexion at all angular velocities. The results indicate that peak torque values of knee flexors and extensors varied differently in trained youth soccer players depending on muscle group and movement velocity with statistically significant changes in knee flexors only.Cilj je ovog istraživanja bio utvrditi varijacije tijekom sezone u snazi pregibača i opružača potkoljenice vrhunskih treniranih mladih nogometaša. Igrači (n=16; dob 16,7±0,7) su testirani na kraju natjecateljske sezone, na početku prijelaznog perioda te tijekom šestog tjedna nove natjecateljske sezone. Izokinetički koncentrični vršni moment sile mjerio se pri brzinama od 60°/s, 180°/s i 360°/s u sjedećem položaju ispitanika. Opseg pokreta se tijekom testiranja kretao od 10 do 90° fleksije koljena. Igrači su izveli seriju od šest maksimalnih ponavljanja prvo dominantnom, a onda i nedominantnom nogom. Prosječne vrijednosti vršnog momenta sile značajno su se mijenjale tijekom promatranih perioda. Značajne razlike (p<0,05) u snazi pregibača potkoljenice zabilježene su između sva tri mjerenja pri sve tri brzine izveđonja. Post hoc test je također potvrdio značajno povećanje snage pregibača potkoljenice između prvoga i drugog mjerenja za dominantnu (180°/s; p=0,033) i nedominantnu (360°/s; p=0,004) nogu. Značajno povećanje vršnog momenta sile pregibača potkoljenice obje noge pri svim brzinama također je zabilježeno između drugoga i trećeg mjerenja. Rezultati pokazuju da vršni moment sile pregibača i opružača potkoljenice različito varira kod treniranih mladih nogometaša ovisno o mišićnoj grupi i brzini pokreta, sa statističkom značajnošću promjena samo za pregibače potkoljenice

Seasonal variation in isokinetic peak torque in youth soccer players

The aim of the study was to investigate the seasonal variation in the strength of the knee flexors and\ud extensors in highly trained youth soccer players. The players (n=16; age 16.7±0.7) were measured at the end\ud of the competitive season, at the beginning of the off-season and during the sixth week of a new competitive\ud season. Isokinetic concentric peak torque was measured at 60°·s-1, 180°·s-1, 360°·s-1 in a sitting position. The\ud testing range of motion was set from 10–90° of knee flexion. Players performed a set of six maximal repetitions\ud for both the dominant and non-dominant limb. Average values of peak torque significantly changed during\ud the observed periods. Significant differences (p<.05) between the three measurement sessions were noted\ud with respect to the knee flexors at all angular velocities. A post-hoc test confirmed a significant increase\ud between the first and the second measurement for flexion in both the dominant (180°·s-1; p=.033) and nondominant\ud legs (360°·s-1; p=.004). A significant increase was also found between the first and the third session\ud for both limbs during the knee flexion at all angular velocities. The results indicate that peak torque values\ud of knee flexors and extensors varied differently in trained youth soccer players depending on muscle group and movement velocity with statistically significant changes in knee flexors only

Self perception of decision making competence in spanish football players

Background: It is known that competence to make decisions is a fundamental aspect of sport competition. Objective: This study has analyzed the decision profile of a sample of Spanish football players of different levels of expertise. Methods: 690 Spanish football players of national and international level completed the decision making questionnaire, which cover three dimensions ? perceived decision competence, decision anxiety and commitment with decision learning. MANCOVA and ANOVA analysis were carried out to analyse the differences in each dimension based on the level of expertise. Results: Results showed that perception of decision making competence increased and the anxiety decreased with the level of expertise. Conclusions: This study confirmed the usefulness of this questionnaire in the process of training for coaches and sport psychologists

The influence of age and maturation on trajectories of stretch shortening cycle capability in male youth team sports

Purpose: To examine the the influence of growth and maturation in the trajectory of stretch shortening cycle (SSC) capability. Method: Using a mixed longitudinal design absolute and relative leg stiffness, and reactive strength index (RSI) were measured three times over a three-year period in 44 youth team sport players. Maturation was determined as maturity-offset and included within the Bayesian inference analysis as a covariate alongside chronological age. Results: Irrespective of age and maturation there was no change in absolute leg stiffness, however relative leg stiffness decreased over time. Maturation and age reduced this decline, but the decline remained significant (BF10 = 5097, model averaged R2 = 0.61). RSI increased over time and more so in older more mature youth players (BF10 = 9.29e8, model averaged R2 = 0.657).. Conclusion: In youth players who are at/post peak height velocity, relative leg stiffness appears to decline, which could have an impact on both performance and injury risk. However, RSI increases during this period, and these data reinforce that leg stiffness and RSI reflect different components of SSC capability. Practitioners should consider these differences when planning training to maximise SSC capability during growth and maturation in athletes on the developmental performance pathway

Effects of attentional focus instructions on the learning of a target task: a moderation role of visual feedback

The present study examined whether visual feedback can have a moderating effect on the relation between attentional focus instructions and the learning of a target movement skill. Participants (N: 100, mean age: 21.0 years, SD: 2.1) were randomly assigned into visual feedback versus non-visual feedback groups. Each group was split into five subgroups: control, internal focus on the arm, and three external focus groups including focus on the dart, on the flight of the dart, and on the bull’s-eye. Participants in each subgroup were asked to throw the darts at the dartboard using their specified focus instructions with either full-visual or nonvisual information on results. The accuracy scores of throws were analyzed in 2 (visual groups) x 5 (focus subgroups) x 6 (trial blocks) analysis of variance with repeated measures on the last factor in acquisition, and 2 (visual groups) x 5 (focus subgroups) analysis of variance in retention and transfer. While the attentional focus instructions were not confirmed as a significant factor in practice, visual feedback was more beneficial than non-visual feedback in the acquisition of a target task. However, the benefits of practicing with visual feedback were not observed in the retention and transfer tests when vision was available. Furthermore, external focus on the flight of the dart was more beneficial than the other attentional focus instructions in transfer test, showing that the optimized distance of external focus of attention for the learning may change when a target task is executed on a stable or variable (moving) target

The visual reaction time distribution in the tasks with different demands on information processing

Background:Reaction tests are a part of the neuropsychological assessment of the individual. The design of these tests and selection of the appropriate measures of reaction time (RT) should come out from the distribution qualities of RTs. According to the newer general theory of RT distribution, the quality of RTs also depends on the specific properties of a reaction task. Objective:The aim of the study was to examine the dependency of RT distribution on an amount of processed information in a visual reaction test, and to verify the stability of RT distribution between two series of RTs in male adolescents. Methods: 25 male adolescents, aged 17.1&#8239;&#177;&#8239;1.1 years, performed four different eye-hand visual reaction tests which differed in a number of choices - simple reaction test (RT1), two, three and four-choice RT tests (RT2, RT3, RT4). Each test involved 2 series with 20 reaction trials in each series, using the computer-based reactometer device. The first, second and third moments of the RT distribution were assessed - the measures of central tendency (mean, median), variability (% CV, median absolute deviation/median ratio - MAD/Mdn, interquartile range) and normality (Kolmogorov-Smirnov test, skewness and kurtosis coefficient &#945; and &#946;). Significance of differences of RTs was assessed by the Wilcoxon test (&#945;&#8239;=&#8239;.05). Results: The analysis showed the non-Gaussian distributions of RTs (&#945;&#8239;=&#8239;.01) with the skew to the right (&#945;&#8239;=&#8239;1.18-4.38) and leptocurtic distribution (&#946;&#8239;=&#8239;1.89-34.15) in all types of the RT tests. The measures of RT variability % CV and MAD/Mdn (%) were lower for the RT1 test as compared to the RT2, RT3 and RT4 tests. No significant differences in RTs measured in the 1st and 2nd series of trials were found in the RT1 test and RT2 test in contrast to significantly shorter RTs in the 2nd series of trials in the RT3 test and RT4 test (p =&#8239;.006 and p &lt;&#8239;.001). RTs measured in the 2nd series of trials of RT1, RT2 and RT4 tests manifested distribution with a higher skewness to the right and higher peakedness than the RTs in the 1st series. Conclusions: The study supported the hypothesis on asymmetric distribution of RTs, specifically when measured in the both eye-hand visual simple and multiple-choice reaction tasks with two up to four choices. Thus, the nonparametric statistics show to be more appropriate for analysis of RTs than the parametric statistics. For both clinical and research purposes, the two series of twenty reaction trials in a computer-based test can provide a sufficient number of the RT data for reliable assessment of visual simple and choice-reaction abilities in the male adolescents

Movement Assessment Battery for Children - second edition: Cross-cultural comparison between 11–15 year old children from the Czech Republic and the United Kingdom

<strong>BACKGROUND</strong>: With the exception of specific clinical methods, no widely used diagnostic tool for motor development assessment of children exists in the Czech Republic. The Movement Assessment Battery for Children – second edition (MABC-2) seems to be one the most developed instruments for children's motor coordination assessment. However, to use it in the Czech population of children in educational and psychological practice including physical education, the cross-validity of the test battery needs to be examined. <strong>OBJECTIVE</strong>: The aim of the study was to make a comparative analysis of performance in motor tasks of the MABC-2 measured in a Czech sample of 11–15 year old children and the United Kingdom (UK) normative sample from which the norms of the MABC-2 were established. <strong>METHODS</strong>: The Czech sample of 11–15 year old children (total n = 589; 310 boys, 279 girls) formed from a random selection of schools from all the geographical regions of the Czech Republic and all size categories of municipalities, was tested by the MABC-2. The results were compared to the performance of the UK normative sample of the same age (n = 344) reported in the MABC-2 Examiner's Manual by Henderson et al. (2007). For this comparative analysis, the effects size coefficient (d) and the z-test were used. <strong>RESULTS</strong>: From three manual dexterity tests of the MABC-2, mean performance of the Czech sample in the Drawing trail test was shown to be significantly higher than the mean performance of the UK sample in all the age groups of both genders (d = 0.68–1.32; p < 0.01). On the other hand, the Czech sample demonstrated no significant differences of performance in the gross motor coordination tests as compared to the performance of the UK sample. Regarding balance assessment, performance in the Two-board balance test (static balance) was found to be significantly higher in almost all the age groups of Czech girls (d = 0.52–0.70, p < 0.01), while Czech boys showed a significantly higher performance only in the Zig-zag hopping test (dynamic balance) at the ages of 14 and 15 years, as compared to the UK sample. In 1.9% of boys and 0.7% of girls in the Czech sample significant motor difficulties were identified (total test score ≤5th percentile). <strong>CONCLUSIONS</strong>: The study revealed that the MABC-2 is valid only for assessment of gross motor coordination in Czech children, but not for assessment of manual dexterity and balance. Before the use of this test battery for Czech children for both practical and research purposes, an adjustment of the norms is needed for the Drawing trail test, Two-board balance test and Zig-zag hopping test