George Vagenas

Harokopion University of Athens, Athínai, Attica, Greece

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Publications (7)8.14 Total impact

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    Charilaos Tsolakis · Emmanuela Kostaki · George Vagenas
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    ABSTRACT: This study investigated selected structural correlates of fencing performance. 33 elite fencers were tested on (a) selected anthropometric, flexibility, and strength-power related parameters, and (b) specific lower extremity functional fencing tests. Multiple regression showed that drop jump and thigh cross-sectional area were best predictors of lunge time and distance of squat jump on the shuttle test. When the two performance variables were expressed per Lean Body Mass, lunge time was significantly predicted only by the performance on the arm-driven counter-movement jump, while time on the shuttle test was best predicted by three noncollinear significant predictors: squat jump performance, thigh circumference, and percent body fat. Lunge time and time on the shuttle test were predicted by explosive power, while none of the nontrainable anthropometric measures or years of training seemed to be important in performance of fencing-related skills.
    Full-text · Article · Jun 2010 · Perceptual and Motor Skills
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    Charilaos Tsolakis · George Vagenas
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    ABSTRACT: The present study aimed at investigating the differences in selected anthropometric, strength-power parameters and functional characteristics of fencing performance between elite and sub-elite fencers. Thirty-three fencers (18 females and 15 males) from the Greek National Team, (age 19 ± 3.5 yr, body height 175.6 ± 7.6 cm, body mass 66.1 ± 9.1 kg, systematic training 8.4 ± 2.9 yr) were classified as elite and sub-elite, according to their international experience. Subjects underwent a detailed anthropometric assessment and performed selected leg power and fencing-specific tests. Significant differences were observed between the two groups in sitting height, triceps, subscapular, and quadriceps dominant skinfold thickness, absolute and body mass-dependent expressions of leg functional power characteristics of fencing performance: "time of lunge" and time of the "shuttle test". Anthropometric traits, such as height, body mass, percent fat and limb length were not different among elite and sub-elite fencers. Although technical and tactical factors are good indicators of fencing success, the observed differences in functional fencing performance tests among different levels of fencers are useful for the design of effective talent development and training-conditioning programs for competitive fencers.
    Full-text · Article · Mar 2010
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    ABSTRACT: This study examined the effects of a typical fencing training program on selected hormones, neuromuscular performance, and anthropometric parameters in peripubertal boys. Two sets of measurements, before training and after 12 months of training, were performed on 2 groups of 11- to 13-year-old boys. One group consisted of fencers (n = 8), who trained regularly for the 12-month period, and the other group (n = 8) consisted of inactive children of the same age. There was no difference in Tanner's maturation stage of the 2 groups before (controls, 2.5 ± 0.3; fencers, 2.1 ± 0.3) and after the 12 months (controls, 3.0 ± 0.3; fencers, 3.0 ± 0.3). Serum testosterone, growth hormone, sex hormone binding globulin, free androgen index, and leptin changed significantly over time, reaching similar values in the 2 groups at the end of the study. Significantly greater increases in body mass (16 ± 3%) and leg cross-sectional area (CSA) (32 ± 7%) were observed only in the fencers' group, and these differences disappeared when height was set as a changing covariate. Although there was a greater increase in height for the fencers compared to the control group (8.6 ± 1.2 vs. 3.6 ± 0.9 cm, p < 0.01), the height reached at the end of the study was almost identical in the 2 groups (controls, 163.6 ± 5.1; fencers, 165.4 ± 2.8). Arm CSA, handgrip strength, and vertical jump performance changed significantly over time for both groups, with no differences between groups. It was concluded that a typical fencing training program for peripubertal boys did not have any effect on selected growth and anabolic hormones and did not influence the normal growth process, as this was reflected by changes in selected anthropometric and neuromuscular performance parameters. This may be because of the characteristics of the present fencing training program, which may not be adequate to alter children's hormonal functions in such a way as to override the rapid changes occurring during puberty.
    Full-text · Article · Nov 2006 · The Journal of Strength and Conditioning Research
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    C. Tsolakis · G.C. Bogdanis · G. Vagenas
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    ABSTRACT: The aim of this study was to establish an anthropometric profile of young fencers separated into four different age groups and to examine the degree of upper and lower limb asymmetry. Selected anthropometric characteristics were measured in 152 fencers (84 males and 68 females) during the Greek fencing championships. Fencers were divided into 4 age categories (boys/girls, cadets, junior and senior) according to the International Fencing Federation rules. The larger differences in anthropometric characteristics of both males and females were observed between the very young group (10-13yrs) and the older groups, while for most parameters, there were no differences between the two older groups (18-20yrs and >20yrs). There was no significant difference between the 10-13yrs groups of males and females in almost all anthropometric characteristics. Somatotype ratings were relatively stable across age groups. The mean somatotype of male fencers was 3.1-2.6-3.2. The female fencers were mainly situated in the ectomorph -endomorph region, and had a mean somatotype of 3.8-1.8-3.3. Arm CSA was higher in males compared to females in all age groups, except for the 10-13yrs group. However, leg CSA was not different between genders in all age groups. Significant CSA asymmetries were observed between the dominant and the non-dominant sides in the arm and leg in both genders. Arm asymmetries were evident from an early age, while leg asymmetries were not observed in the younger group. The lack of significant differences between males and females for the 10-13yrs groups in most of the anthropometric characteristics, should be taken into account in talent selection.
    Full-text · Article · Jan 2006 · Journal of Human Movement Studies
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    ABSTRACT: Nineteen untrained preadolescent males (11-13 years old) were randomly placed into an experimental trained group (STG, n = 9) and a control group (n = 10). Informed consent was obtained from the children and their parents. The STG was submitted to a 2-month resistance-training program (6 exercises, 3 x 10 repetitions maximum [RM], 3 times per week), followed by a 2-month detraining program. The effectiveness of the resistance program was determined by measuring pre- and posttraining and detraining differences in isometric and isotonic (10RM) strength and hormonal responses in testosterone (T), sex hormone binding globulin, and free androgen index (FAI). Their maturation stage was evaluated according to Tanner. Significant posttraining isometric strength gains (17.5%) and mean T and FAI value increases (p < 0.05-0.001) were observed in STG. Detraining resulted in a significant loss (9.5%, p < 0.001) of isometric strength whereas the hormonal parameters of STG remained practically unaltered. The relative (delta%) postdetraining hormonal responses correlated significantly with the respective isometric strength changes. In conclusion, the resistance training induced strength changes independent of the changes in the anabolic and androgenic activity in preadolescent males. Further research is needed to fully clarify the physiological mechanisms underlying the strength training and detraining process.
    Full-text · Article · Aug 2004 · The Journal of Strength and Conditioning Research
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    ABSTRACT: The purpose of this study was two fold a) to determine the levels of hormonal parameters which are related to growth and sexual maturation (T, SHBG, FAI, GH) in 66 pre-pubertal and early-pubertal boys (11-13 years old) who systematically engage in individual and team sports activities of endurance, strength, speed and skill, respectively, and b) to investigate the effect of two different forms of exercise namely aerobic (AG) and weight training (WG) on androgen levels in 19 sedentary pre-pubertal boys. The control groups (CG) consisted of boys of the same age who attended only the school physical education programmes. The individuals included in the study participated voluntarily after their parents had been informed and had given their written consent. Hormonal concentrations were determined using radioimmunoassay and immunoradiometric assays. No differences were observed among the various athletes' groups as regards Tanner stages, height and weight. The mean T and FAI values of the control group did not differ from those of the corresponding athletes group. Significant differences were observed among the groups regarding BMI, % body fat, T, SHBG, FAI and GH (p<0.05). T and FAI values in the WG group were significantly higher than the corresponding concentrations: a) in the AG group by 338 and 609%, p<0.05 and b) in the control group CG by 91 and 96%, p<0.05, respectively. The hormonal differences detected among the various groups of athletes must be attributed as much to the type of physical exercise and to developmental factors as to the selection criteria used for the different athletic talents. The importance of the specificity of training stimulus in the hormonal adaptations of pre-pubertal sedentary subjects was demonstrated.
    No preview · Article · Apr 2003 · Hormones (Athens, Greece)
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    ABSTRACT: We investigated hormonal regulators of growth and development, leptin levels, body composition, neuromuscular performance, and the associations among them in trained prepubertal athletes (experimental group [EG]) and an untrained control group (CG). Informed consent was obtained from the children and their parents. Their maturation stage was evaluated according to Tanner's criteria. There were no differences between EG and CG in physical characteristics, body mass index (BMI), lean body mass, testosterone (T), sex hormone-binding globulin, free androgen index, growth hormone (GH), hand grip strength, and jumping performance. Leptin levels and percent fat of the EG were significantly lower than those of the CG (p < 0.05-0.005). Leptin levels were significantly correlated to body fat and BMI for both the EG and the CG (r = 0.51-0.79). There is little evidence that leptin has a positive effect on growth and anabolic factors. Sex hormone-binding globulin and GH may explain the variation of leptin in athletes with low T (R(2) = 0.43) and in CG (R(2) = 0.35), respectively. Leptin seems to be a permissive factor for the onset of puberty, and the training background needs an optimal biological maturation to produce significant differences in muscle and power performance.
    No preview · Article · Mar 2003 · The Journal of Strength and Conditioning Research