1,721,041 research outputs found
La Riabilitazione Motoria negli Sport Invernali mediante potenziamento Muscolare con Regime Eccentrico
No full textAn experimental test of the local fluctuation theorem in chains of weakly interacting Anosov systems
No full textAn experimental test of a large fluctuation theorem is performed on a
chain of coupled ``cat maps''. Our interest is focused on the behavior
of a subsystem of this chain. A {\it local} entropy creation rate is
defined and we show that the local fluctuation theorem derived in
\cite{Ga1} is experimentally observable already for small subsystems,
\ie the finite size effects, for which the theory says little, are
small even in small subsystems of the systems considered
Is self-administered rating scale for pubertal development a predictor of countermovement jump in young soccer players?
Full text linkObjective: Considering that in Young sport competitions children are divided according to their chronological age, the aim of this study was to examine the correlation among chronological age and Self-Administered Rating Scale for Pubertal Development (PDS), anthropometry (Body Mass Index -BMI-, percent body fat -%BF-, fat free mass -FFM-), and Countermovement jump (CMJ) measures. Methods: 112 young soccer players (age: 14±2 yrs; height: 1.68±0.11 m; weight: 60.3±11.6 kg; BMI: 21.3±2.5 kg.m-2) grouped in “Giovanissimi” (12-14 yrs), “Allievi” (15-16 yrs), and “Juniores” (>17 yrs), categories were evaluated. Pearson correlations and stepwise multiple regression analysis among variables were calculated considering all subjects and within categories. The internal consistency of PDS was determined by Cronbach’s α coefficient (Cα). Considering all subjects, PDS showed an excellent Cα (0.89) and significant correlations with sub-category (r=0.66), age (r=0.67), %BF (r=-0.31), FFM (r=0.71), and CMJ (r=0.55). Within “Giovanissimi” category, significant correlations were found between PDS and age (r=0.56), CMJ (r=0.33), FFM (r=0.63), and subcategory (r=0.55). In “Allievi”, PDS showed correlations with CMJ (r=0.46), FFM (r=0.42), and %BF (r=-0.45). In “Juniores” no significant correlations between PDS and other variables were present. The regression model with sub-category, PDS, and %BF as predictors explained 41% of the variance of CMJ in all subjects. In the “Allievi” category the PSD was the only predictor explaining the 18% of the CMJ performance variance. Results: PDS can provide useful information for the coach to create individual conditioning programs taking into account the growth problems of young soccer players and to minimize the risk of an excessive workloa
Effects of Coordination training in amateur soccer players
No full textEgan, et al. (2007) showed that skilled players tend to score more during a moving-ball condition than during a dead-ball condition
with respect to their less skilled counterpart. The aim of study was to evaluate the effects of 10-week of coordination training (CT)
on physical and soccer abilities in amateur soccer players. Seventeen amateur soccer players participated to study and they randomly divided into two groups: Experimental Group, (EG; n:8; age: 23 ± 5 yrs: weight: 75.0 ± 8.2 kg; height: 181.1 ± 11.5 cm; BMI: 22.9 ± 1.1 kg m2) and Control Group (CG; n: 9; age: 24 ± 4 yrs, weight: 71.1 ± 5.9 kg, height: 176.6 ± 5.0 cm; BMI: 22.8 ± 1.2 kg m2). Both groups continued technical and tactical soccer training together three days (120 minutes/day) a week. EG attended additionally CT (rhythm and soccer specific coordination exercises) through 10-week, 2 days per week, 20 minutes session duration. After 10 week, playing time, physical (YO–YO IR1, counter movement jump—CMJ), and soccer ability (shooting a dead ball, and shooting from a pass) test were compared (p.05). No anthropometric significant differences emerged between groups. Between groups, no differences emerged in playing time, physical, and soccer ability test. After 10 week, the results showed statistical different only in YO–YO IR1 (p.001) and CMJ
(p.005) of each groups. To our knowledge, the current study is the first attempt to investigate the effect of a regular CT in soccer players. Considering the results of this study and that, during matches, player constantly adjust his body coordination (i.e. in relation to ball speed and ball position, and the intent of the task goals), further studies are needed to fully elucidate the effects of CT on performance and injuries
Relationship among explosive power, body fat, fat free mass, and pubertal development in youth soccer players. A preliminary study
No full textPurpose Changes in body size and functional capacities
are highly individual during puberty, and the performance
of a soccer player is often closely related to their maturity
status. The aim of the study was to evaluate the relationships
among explosive power, body fat, fat free mass and
pubertal development in young soccer players.
Methods Explosive power (countermovement jump—
CMJ), body mass index (BMI), percentage of body fat
(%BF), fat free mass (FFM) and a Self-Administered
Rating Scale for pubertal development (PDS) values of 11
‘‘Giovanissimi’’ (age 13 year), 13 ‘‘Allievi’’ (age 15 year)
and 10 ‘‘Juniores’’ (age [17 year) male soccer players
were compared. The statistical analysis was performed
using an analysis of variance among categories with
Fisher’s post hoc as appropriate. Furthermore, Pearson
correlations among variables were calculated considering
all subjects and also within categories.
Results Statistical differences emerged among categories
in CMJ (F(2,30) = 28.3, p\0.01), body fat weight (F(2,31) =
29.2, p\0.01) and PDS (F(2,29) = 18.5, p\0.01), while
%BF values showed statistical differences only for ‘‘Giovanissimi’’
and ‘‘Juniores’’ (F(2,31) = 3.4, p = 0.01). CMJ
showed significant correlations with FFM (r = 0.68) and
PDS (r = 0.63), PDS with FFM (r = 0.66) and BMI with
%BF(r = 0.71) and FFM (r = 0.71).A high correlation was
found within categories.
Conclusion Since we found differences between categories
and no correlation between chronological age and
pubertal status, this study highlights the importance of
assessing of puberty in youth soccer team
Relationship among Repeated Sprint Ability, Chronological Age and Puberty in young soccer players
No full textThe aim of this study was to analyzed the relationship of repeated sprint ability (RSA) with chronological age and puberty in 100 young soccer players (age: 13 ± 3 years–160 ± 33 months-; height: 159 ± 16 cm, mass: 49.7 ± 14.1 kg; body mass index [BMI] 19.2 ± 2.5 kg/m2) grouped on “Pulcini” (9–10 years), “Esordienti” (11–12 years), “Giovanissimi” (13–14 years), “Allievi” (15–16 years), and “Juniores” (.17 years) categories. Anthropometric (weight, height, BMI), RSA (7 x 30 m sprint with 25 seconds active rest: total time—TT, the lowest sprinting time, and the fatigue index percentage—%IF), and development (self-administered rating scale for pubertal development PDS; puberty) parameters were measured. ANOVA among categories was applied to asses differences (p ≤ 0.05) in TT and %IF. When a significant effect was found, Bonferroni’s post hoc analysis was used. Pearson correlation among all variables was calculated considering all subjects and also within categories. Among categories, statistical analysis showed significant differences (p< 0.001) in TT
and a considerable trend toward significance (p = 0.06) in %IF. Significant correlations among variables were found in all subjects
and within categories. In particular, TT showed large significant correlation with PDS (r = 0.66) and puberty (r = 0.67) only in “Esordienti.” This study provides useful information for the coach to propose an appropriate training and to obtain the optimal training effect and to minimize the risk of injury and overtraining during the different phases of growth and maturation
Relationship among repeated sprint ability, chronological age, and puberty in young soccer players
No full textThe aim of this study was to analyzed the relationship of repeated sprint ability (RSA) with chronological age and puberty in 100 young soccer players (age: 13 6 3 years–160 6 33 months-; height: 159 6 16 cm, mass: 49.7 6 14.1 kg; body mass index [BMI] 19.2 6 2.5 kg/m2) grouped on “Pulcini” (9–10 years), “Esordienti” (11–12 years), “Giovanissimi” (13–14 years), “Allievi” (15–16 years), and “Juniores” (.17 years) categories. Anthropometric (weight, height, BMI), RSA (7 3 30 m sprint with 25 seconds active rest: total time—TT, the lowest sprinting time, and the fatigue index percentage—%IF), and development (self-administered rating scale for pubertal development PDS; puberty) parameters were measured. ANOVA among categories was applied to asses differences (p # 0.05) in TT and %IF. When a significant effect was found, Bonferroni’s post hoc analysis was used. Pearson correlation among all variables was calculated considering all subjects and also within categories. Among categories, statistical analysis showed significant differences (p , 0.001) in TT and a considerable trend toward significance (p = 0.06) in %IF. Significant correlations among variables were found in all subjects and within categories. In particular, TT showed large significant correlation with PDS (r = 20.66) and puberty (r = 20.67) only in “Esordienti.” This study provides useful information for the coach to propose an appropriate training and to obtain the optimal training effect and to minimize the risk of injury and overtraining during the different phases of growth and maturation
RSA response to preseason training in semiprofessional soccer players
No full textAbstract This study has investigated the effect of 8 weeks of preseason training on the repeated sprinting ability (RSA) in semiprofessional soccer players (SPSP). An RSA test, consisting of 7 9 30 m sprint with 25 s active rest, was administered to 12 SPSP (age 23 ± 6 years) pre- and post-8 weeks of preseason soccer training. Preseasonal training consisting of aerobic sessions (high-intensity intermittent training) was provided three times a week on alternate days with the strength training sessions (basic and functional strength training) and sprint training drills. Analysis of variance for repeated measures was conducted to assess differences (p.05) in RSA test and fatigue index with time (i.e., pre-post) as within factor. Multivariate analysis of variance, with the seven repeated sprint tests as dependent variables and time (i.e. pre-post) as within factor, was conducted to test differences in sprint performance over the time. The main effect (p.001) was found before (pre-) and after (post-) the preseasonal training in global RSA performance;
conversely, no statistical differences were found between fatigue index values. An overall significant effect was found for the seven sprints performed pre- and post. Univariate
analysis shows that each sprint time was significantly (p.001) lower in the pre- than in the post-RSA tests. This study provides useful information for the coach to understanding the training process of SPSP and to maximize the best physical condition of the whole team
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