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EN
Reference values (norms) of many somatic variables are indispensable in diverse areas, e.g. medicine, sports, armed forces, etc. Such norms are usually presented as means and standard deviations or as lower/upper limits for various age categories of given sex and mostly represent population values instead of being related to body size.The aim of this paper is to present the most common errors in the process of establishing norms, not only those related to somatic measurements. A set of rules is proposed that may greatly facilitate that process and make the resulting norms rational and reliable.
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EN
Study aim: contemporary military activities call for extremely high coordinative motor skills, especially precision, attention focusing and motor adjustment. No obligatory tests assessing those skills are presently used by Polish armed forces. The aim of this study was thus to set up a procedure of assessing running skills involving coordination and motor adjustment, possible to be of military use. Material and methods: a group of 68 male students aged 22–25 years (23.42 ± 2.1 years) volunteered to participate in the study. The following tests were applied: 15-m sprint, shuttle run 3 × 5 m, 15-m slalom run and 15-m squat (on all fours). The tests were applied twice. The sums of all 4 velocities served as the dependent variable; its total variance was partitioned into percent contributions of the standardised results of 4 running tests. Results: it turned out that the total variance was explained in 95% by the 15-m sprint and 15-m squat nearly by half the contributions of the other two variables being non-significant. Two indices were constructed: Speed-strength index (W1) and Speed-agility index (W2). Discussion: the proposed indices representing the speed-strength and speed-agility potentials seem to adequately reflect running-related features required of soldiers performing field tasks. Those indices may also find use in monitoring motor skills of team game players, including their selection.
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Body image of adolescent boys

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EN
Study aim: To compare the perception of own body by adolescent boys with an external assessment. Material and methods: Two groups of boys (45 from Warsaw, aged 15 – 16 years, and 49 from a small town in South- Eastern Poland, aged 16 years) were studied by using standard body image templates containing 9 shapes. Every boy indicated the perceived shape and that he wished to have. The external assessment was done by the same investigator and that assessment served to classify boys as underweight (n = 4), normal (n = 51) or overweight (n = 39; Shapes 1 – 2, 3 – 4 and 5 – 9, respectively) and to correlate the scores with BMI. Results: The external and self-assessments were concordant in overweight boys, the desired shapes being significantly lower only in Group 1. The percentage of overweight boys was significantly (p<0.05) higher in Group 1 than in Group 2. “Normal” boys from Group 1 significantly (p<0.001) overrated their body shape compared with external rating. External ratings of body shape significantly correlated with BMI values in both groups alike (r = 0.82, p<0.001). Conclusions: The presented approach to body shape studies may contribute to preventing biosocial disorders in adolescent boys brought about by thoughtless striving for an ideal shape promoted by mass media.
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EN
Study aim: To assess the anaerobic endurance of untrained male and female subjects by applying repeated maximal exercises.Material and methods: Untrained male subjects aged 23 - 27 years (n = 17, body height 170 - 197 cm, body mass 65 - 110 kg) and female ones aged 20 - 25 years (n = 10, body height 168 - 184 cm, body mass 55 - 86 kg) performed 6 maximal cycle ergometer (CE) exercises (64 flywheel revolutions each, spaced by 15 s intermissions, the load amounting to 75 g per kg body mass) and 6 bouts of 10 push-offs on an inclined plane device (IP). Mean and maximal relative power outputs were recorded, the ratio of the two - the performance index (PI), served as a measure of anaerobic performance.Results: Men attained significantly higher maximum power outputs than women in both tests but the respective PI values were in both genders alike. Highest power outputs amounted to 10.80 ± 0.91 and 9.45 ± 0.43 W/kg (cycle ergometer) for men and women, respectively, and to 20.06 ± 3.78 and 13.70 ± 1.88 W/kg (inclined plane) for men and women, respectively. No significant differences between genders were found for the PI values in either test but significant within-gender differences were detected between tests: mean PI values (±SD) amounted to 0.799 ± 0.052 and 0.850 ± 0.063 for men (p<0.01), and 0.803 ± 0.030 and 0.875 ± 0.078 for women (p<0.05), for CE and IP, respectively.Conclusions: The performance index enabled comparing male and female subjects, as well as different exercise tests consisting of repeated, short, maximal exercises, with respect to anaerobic endurance.
EN
Purpose.The purpose of the study was to assess anaerobic endurance in volleyball players through repeated vertical jump performance under quiet and noisy conditions. Methods. A group of 12 female players aged 19-28 year completed six sets of eight standing vertical jump jumps; jump height and heart rate before and after the protocol were measured in quiet and noisy (fan cheering) conditions. Results. Maximum and minimum vertical jump heights were higher and intragroup differences were smaller in noisy than quiet conditions. Conclusions. Vertical jump testing, a measure of physical activity typical of volleyball, is suitable for monitoring training effects. The influence of noise typical during volleyball matches had a positive effect on player performance and anaerobic endurance.
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Content available remote

Prevalence of iron deficiency in male elite athletes

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EN
Study aim: To assess the prevalence of iron deficiency in competitive male athletes.Material and methods: In total, 90 elite athletes practicing judo, rowing, pentathlon, volleyball, kayaking and biathlon, aged 16-33 years, were studied. Blood morphology indices: haemoglobin concentration (Hb), hematocrit (Hct), red blood cell count (RBC), leucocyte count (WBC), mean corpuscular haemoglobin concentration (MCHC), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) were determined. The concentrations of ferritin, soluble transferrin receptor (sTfR) and iron, as well as total iron binding capacity (TIBC), were determined in serum. Additionally, erythropoietin (EPO) was assayed in subjects with elevated sTfR levels.Results: In no case iron-deficiency anaemia was found, but in 43% of subjects iron deficiency was detected. This included first stage of iron deficiency (iron depletion; ID) in 13% of subjects (ferritin <20 μg/L), and iron-deficient erythropoiesis (IDE) in 30% of subjects (ferritin <16 μg/L and sTfR> 2.75 mg/L). In all subjects with IDE, the concentrations of EPO were within normal range. The haematological indices remained unaffected in iron-depleted subjects, but in iron-deficient erythropoiesis subgroups the mean values of haemoglobin concentration and hematocrit were significantly lower than in subjects with normal iron stores (NIS).Conclusion: Despite the lack of anaemia among studied athletes, the incidence of latent iron deficiencies (iron depletion and iron-deficient erythropoiesis) was very high. The increasing incidence of iron deficiency, together with apparent decreases of haematological indices in subjects with iron-deficient erythropoiesis, markedly augments the risk of anaemia in young, competitive male athletes. Therefore, that category of subjects should be periodically screened for iron deficiency.
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