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Open access

Agata Grenda, Marek Sawczuk, Mariusz Kaczmarczyk, Agnieszka Maciejewska, Danuta Umiastowska, Wioletta Łubkowska, Piotr Żmijewski and Paweł Cięszczyk

Abstract

Single nucleotide polymorphism C825T located within the GNB3 gene has been proposed in the literature as the performance enhancing polymorphism in highly trained athletes. Therefore, the aim of the present study was to verify the hypothesis assuming an association between the C825T polymorphic site and performance of competitive swimmers. The frequencies of C/T alleles and distribution of CC, CT and TT genotypes of the C825T GNB3 polymorphism were compared between athletes and nonathletic controls as well as between sprint and endurance swimmers. Genomic DNA was extracted from 197 competitive swimmers (50 long distance swimmers (LDS) and 147 short distance swimmers (SDS)) and 379 sedentary volunteers. The allele frequencies and genotype distribution of the C825T polymorphic site were not significantly different when LDS and SDS were compared to sedentary controls. Gender-specific analysis did not reveal any significant differences in allele and genotype distribution, neither between female controls and female swimmers nor between male controls and male swimmers. No significant differences in allele frequencies and genotype distribution were observed when LDS and SDS as well as groups of swimmers stratified by gender were compared. The results of this study do not support the hypothesis that the C825T polymorphism of the GNB3 gene is associated with swimming performance in competitive swimmers.

Open access

Marcel Răsădean

Abstract

Introduction: Masters swimming competitions involve adults who practice swimming as a hobby, and it is focused on three main areas: fitness activity, recreational activity, and competitive activity. Masters swimming competitions are regulated at an international level by the FINA (Federation Internationale de Natation) and by the LEN (Ligue Europeenne de Natation). The Swimming Masters competitions are divided in age groups, starting at the age of 25, as follows: 25-29 years, 30-34 years, 35-39 years etc.

Aim: In this paper we wish to present a study on reduction of swimming speed in relation to age, in breaststroke men competitions (50 m, 100 m, and 200 m).

Methods: We analyzed the swimming speed for Masters Swimmers in a long swimming pool for the following events: 50 m, 100 m, 200 m – man breaststroke. The reference speed for each age group was calculated as the mean of the best 10 times obtained for that certain category.

Results: For competitors aged 60-69 the speed decreases reaching about 80-60% of the maximum speed, and it reaches 80% of the maximum value at ages that range from 70 to 84 years old. After 85 the speed decreases up to 30% to 58% of the maximum speed.

Conclusion: In breaststroke men events the speed at which master competitors swim decreases with age. Regarding the values of speed dependent on age and type of event we can state that it decreases more abruptly for older age in shorter distance events.

Open access

Marcin Jaszczak

The Dynamical Asymmetry of the Upper Extremities During Symmetrical Exercises

Purpose. The purpose of the study was to estimate the influence of the symmetrical movements, mirror (breaststroke) and translational (front crawl) ones, on the dynamical asymmetry of upper limbs. Basic procedures. Thirty six students (15 males and 21 females) took part in the study. The forces produced by the subjects' upper limbs during breaststroke and front crawl simulation on the swimming ergometer (Weba, Germany) were recorded. Then the coefficient of dynamical asymmetry was computed. Main findings. Breaststroke movements revealed lower dynamical asymmetry of upper limbs than front crawl ones for men as well as for women. Greater differences between the types of movement under study were observed in women. Conclusions. It might appear that males can use interchangeably both techniques during symmetrization. However, for women, first of all the mirror symmetry movements should be used. So, selection of exercises for symmetrization of movements of upper limbs should be based on the gender factor, too.

Open access

Marek Strzała, Piotr Krężałek, Marcin Kaca, Grzegorz Głąb, Andrzej Ostrowski, Arkadiusz Stanula and Aleksander Tyka

The breaststroke kick is responsible for a considerable portion of the forward propulsion in breaststroke swimming. The aim of this study was to measure selected anthropometric variables and functional properties of a swimmer’s body: length of body parts; functional range of motion in the leg joints and anaerobic power of the lower limbs. Chosen kinematic variables useful in the evaluation of swimming performance in the breaststroke kick were evaluated. In the present research, swimming speed using breaststroke kicks depended to the largest extent on anaerobic endurance (0.46, p < 0.05 partial correlations with age control). In addition, knee external rotation and swimming technique index had an impact on swimming speed and kick length (both partial correlations with age control 0.35, p < 0.08). A kinematic analysis of the breaststroke kick hip displacement compatible with horizontal body displacement was significantly negatively correlated with foot slip in the water opposite to body displacement (partial correlations: with leg length control -0.43, p < 0.05; with shank length control -0.45, p < 0.05, respectively). Present research and measurements of selected body properties, physical endurance and kinematic movement analysis may help in making a precise determination of an athlete’s talent for breaststroke swimming.

Open access

Marek Strzała and Piotr Krężałek

The Body Angle of Attack in Front Crawl Performance in Young Swimmers

Among factors influencing frontal (form) resistance in swimming the angle between the swimmer's body and the line of his/her horizontal movement is particularly important. The measurement of this angle called the angle of attack (α) represents indirectly active torque (τa) during swimmer's body movement. Purpose. The aim of the study was to measure the angle of attack in front crawl swimming in young swimmers at long (2000 m), medium (400 m) and short (25 m) distances and to examine the correlation between the angle and swimming speed at those distances. Basic procedures. Swimmers' angles of attack formed between the line of swimmer's movement direction (horizontal direction) and (a) the line connecting the swimmer's hips and goggles (αH-G), and (b) the line connecting the swimmer's hips and shoulders (αH-S) were measured. Main findings. The body angle of attack in front crawl swimming was negatively correlated with swimming speed. In the analysis of αH-G (7.3 ± 2.74°) with swimming velocity at 2000 m the correlation was on the verge of statistical significance (-0.38, p<0.06). Conclusions. The angle of attack index in controlled front crawl swimming races at the distances of 2000, 400 and 25 m was negatively correlated with swimming speed only at 2000 m, and it was smaller in older, more experienced swimmers.

Open access

Małgorzata Stachowicz, Katarzyna Milde and Marcin Janik

Anaerobic endurance of young swimmers aged 12 years

Study aim: To assess the effects of swimming training on anaerobic endurance, swimming velocity and chest girth in children aged 12 years.

Material and methods: Two groups of children aged 12 years were studied. Group S (14 boys and 6 girls) training swimming at a sport-oriented school 3 days a week, 90 min per session, and Group R (6 boys and 6 girls) engaged in competitive swimming for 4 years. Children from Group S were subjected twice (in September and in February) to a swimming test consisting of 6 bouts of swimming the 12.5-m distance, spaced by 30-s intermissions. Mean and maximum swimming velocities in the entire test were recorded together with their ratio (Performance Index, PI). In children from Group R the swimming velocity at one 12.5-distance was recorded.

Results: Apart from somatic indices, significant increases over the 5-month training period were noted in mean swimming velocity in boys and girls (p<0.001) and in maximum velocity in boys (p<0.01). No significant changes were noted in the performance index or in heart rate.

Conclusions: Performance index as a measure of anaerobic endurance may serve as a useful tool in assessing the adaptive performance changes in young swimmers.

Open access

Ricardo Fernandes, João Ribeiro, Pedro Figueiredo, Ludovic Seifert and João Vilas-Boas

Kinematics of the Hip and Body Center of Mass in Front Crawl

The kinematic profiles of the hip and center of mass in front crawl swimming were compared to quantify the error of using a fixed body point to assess intracyclic velocity variations at moderate intensity exercise. The practical goal was to provide a useful tool, easy and fast to assess, and to use as feedback, for assessing swimming efficiency. Sixteen swimmers performed an intermittent incremental protocol that allowed assessing the individual anaerobic threshold velocity. One complete stroke cycle was analysed at the step intensity corresponding to each swimmer's anaerobic threshold. The subjects were videotaped in the sagittal plane using a double camera set-up for two-dimensional kinematical analyses. The hip and the center of mass presented similar mean velocity and displacement values, being highly related to both parameters. However, the hip reflects the center of mass forward velocity and horizontal displacement with 7.54% and 3.24% associated error, respectively. Differences between hip and center of mass were observed for intracyclic velocity variations (0.19±0.05 and 0.25±0.08, respectively, for a p<0.001), and the negative mean error value found (-0.06) evidenced a tendency of the hip to overestimate the center of mass velocity variation. It is possible to conclude that the hips forward movements might provide a good estimate of the swimmer's horizontal velocity and displacement that is relevant for diagnostic purposes, especially to assess swimming efficiency through the intracyclic velocity variations. Nevertheless, the hip point error magnitude should be taken into consideration in data interpretation.

Open access

Grzegorz Bielec

Variants of Development of Sports Career of 11-Year-Old Female Swimmers

Introduction. The development of a sporting career takes a course within a phased manner, the various stages are characterized by different goals and tasks. In competitive swimming there are many cases of athletes who achieved high sporting results in the category of children and youths and who soon after abandoned their interest in training. The aim of this study was to find the association between the sports achievements of 11-year-old girls competing in the 200 m backstroke events and their sports level in the subsequent years of their career. Material and methods. The results of the sporting careers of girls who ranked from 1st to 20th in the 200 m backstroke event in the Polish Correspondence Championships for 10 and 11-Year-Old Children in 2003 were presented. Their positions taken in subsequent editions of the summer Polish championship till 2009 were the criterion of their career development. An analysis of documents was used as a scientific method. The basis for the analysis were post-competition protocols listed on the official website of the Polish Swimming Federation. Results. Only 30% of the examined athletes took part in all main events intended for their age. Less than half of them participated in the Polish 17-18-Year-Old Junior Championships organized within the Nationwide Juvenile Olympics. 40% of the girls from the studied group ended their careers before the age of 15. Four basic variants of development of a sporting career were observed in the group. Conclusions. After analyzing the athletes' careers it can be stated that a high position in the national ranking of 11-year-olds does not guarantee significant sporting achievements in later years. In the studied group of girls the stroke and distance specialization had changed in most cases (80%).

Open access

Elżbieta Biernat

Socio-Demographic Determinants of Participation in Swimming Amongst Working Residents of Warsaw

The aim of research is to assess the correlation between socio-demographic factors and swimming activity among the working population of Warsaw. The questionnaire survey included 4405 randomly selected residents of Warsaw. The correlation between the swimming activity and the variables characterizing the socio-demographic structure of the respondents were assessed by log-linear modelling. The significance of the impact of factors included in the analysis was determined using the chi-square test. Thirty-five per cent of the respondents declared recreational swimming. Gender, age, BMI, education, occupation, and income were significantly related to the swimming activity. Women (33%) - compared to men (38%) - were almost 1.2 times less likely to participate in swimming; similarly, overweight people (33%, OR = 0.90) and obese people (33%, OR = 0.92). People from Warsaw from 20-29 years (43%), with higher education (40%), incomes above the national average (40%), and representing the profession of an actor (52%), swam relatively more often. The results of the study might help in developing marketing plans and market segmentation strategies, as well as in forecasting the development trends of the leisure activity.

Open access

Daniel López-Plaza, Fernando Alacid, Pedro A. López-Miñarro and José M. Muyor

Abstract

The purpose of this study was to determine the influence of different sizes of hand paddles on kinematic parameters during a 100 m freestyle swimming performance in elite swimmers. Nine elite swimmers (19.1 ± 1.9 years) completed three tests of 100 m without paddles, with small paddles (271.27 cm2) and with large paddles (332.67 cm2), respectively. One video camera was used to record the performance during the three trials. The mean swimming velocity, stroke rate and stroke length were measured in the central 10 meters of each 50 m length. The results showed that stroke length tended to increase significantly when wearing hand paddles (p < 0.05) during both the first and second 50 m sections whereas the increase in swimming velocity occurred only in the second 50 m (p < 0.05). Conversely, the stroke rate showed a slight decreasing trend with increasing paddle size. During the 100 m freestyle trial the stroke kinematics were changed significantly as a result of the increase in propelling surface size when hand paddles were worn.