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Swimmers take great advantage by reducing the drag forces either in passive or active conditions. The purpose of this work is to determine the frontal area of swimmers by means of an automated vision system. The proposed algorithm is automated and also allows to determine lateral pose of the swimmer for training purposes. In this way, a step towards the determination of the instantaneous active drag is reached that could be obtained by correlating the effective frontal area of the swimmer to the velocity. This article shows a novel algorithm for estimating the frontal and lateral area in comparison with other models. The computing time allows to obtain a reasonable online representation of the results. The development of an automated method to obtain the frontal surface area during swimming increases the knowledge of the temporal fluctuation of the frontal surface area in swimming. It would allow the best monitoring of a swimmer in their swimming training sessions. Further works will present the complete device, which allows to track the swimmer while acquiring the images and a more realistic model of conventional active drag ones. [ABSTRACT FROM AUTHOR]

Stocking density determines the performance of polyculture. However, the underlying mechanisms of how density affects the behavior of aquaculture animal are still unclear, especially the predation and competition. Here we selected a typical polyculture system containing predator swimming crabs (Portunus trituberculatus) and prey Manila clams (Ruditapes philippinarum), and examined the influence of stocking density on crab predation, competition, and their interactions. Specifically, we calculated the predation rate, and quantified the foraging behavior and encounter behavior between crabs. Results show that, with increasing stocking density, the predation rate significantly decreased as a result of aggressive interactions between crabs (e.g., fighting and threatening). Increased crab density promoted their competition, which was manifested as an increase in the proportion of time spent on aggression. However, the probability of aggressive behavior upon encounter was reduced to avoid time loss and the risk of injury during aggression. Nevertheless, the prolonged aggressive behavior negatively affected the foraging efficiency, as indicated by an increase in the proportion of handling time and a decrease in the probability of consumption upon capture. While the crabs attempted to compensate for the reduced foraging efficiency by significantly increasing the probability of capture upon encounter, the impacts of aggressive interactions outweighed their coping capacity, rendering a reduction in observed predation rates. The revealing of behavioral mechanisms not only provides an improved understanding of how the stocking density affects the behavior of crabs, but also helps to optimize the management of crab-clam polyculture. • Predation rates of crabs on clam decline as its stocking density rises. • Raised stocking density promotes time spent on aggressive interactions among crabs. • Long-term involvement in aggressive interactions disturbs foraging behavior. • The suppression in handling efficiency of crabs on clams reduced the predation rates. • Crabs cope with intense competition using short-term behavioral changes. [ABSTRACT FROM AUTHOR]

Background The key difference between the Olympic and Paralympic Games is the use of classification systems within Paralympic sports to provide a fair competition for athletes with a range of physical disabilities. In 2009, the International Paralympic Committee mandated the development of new, evidence-based classification systems. This study aims to assess objectively the swimming classification system by determining the relationship between passive drag and level of swimming-specific impairment, as defined by the current swimming class. Methods Data were collected on participants at the London 2012 Paralympic Games. The passive drag force of 113 swimmers (classes 3-14) was measured using an electro-mechanical towing device and load cell. Swimmers were towed on the surface of a swimming pool at 1.5 m/s while holding their most streamlined position. Results Passive drag ranged from 24.9 to 82.8 N; the normalised drag (drag/mass) ranged from 0.45 to 1.86 N/kg. Significant negative associations were found between drag and the swimming class (τ=-0.41, p<0.01) and normalised drag and the swimming class (τ=-0.60, p<0.01). The mean difference in drag between adjacent classes was inconsistent, ranging from 0 N (6 vs 7) to 11.9 N (5 vs 6). Reciprocal Ponderal Index (a measure of slenderness) correlated moderately with normalised drag (rP=-0.40, p<0.01). Conclusions Although swimmers with the lowest swimming class experienced the highest passive drag and vice versa, the inconsistent difference in mean passive drag between adjacent classes indicates that the current classification system does not always differentiate clearly between swimming groups. [ABSTRACT FROM AUTHOR]

The study examined the changes of training load and physiological parameters in relation to competitive performance during a period leading to a national championship. The training content of twelve swimmers (age: 14.2±1.3 yrs) was recorded four weeks before the national championship (two weeks of normal training and two weeks of the taper). The training load was calculated: i) by the swimmer's session-RPE score (RPE-Load), ii) by the training intensity levels adjusted after a 7x200-m progressively increasing intensity test (LA-Load). Swimmers completed a 400-m submaximal intensity test, a 15 s tethered swimming and hand-grip strength measurements 34-35 (baseline: Test 1), 20-21 (before taper: Test 2) and 6-7 (Test 3) days before the national championship. Performance during the national championship was not significantly changed compared to season best (0.1±1.6%; 95% confidence limits: -0.9, 1.1%; Effect Size: 0.02, p=0.72) and compared to performance before the start of the two-week taper period (0.9±1.7%; 95% confidence limits: 0.3, 2.1%; Effect size: 0.12, p=0.09). No significant changes were observed in all measured physiological and performance related variables between Test 1, Test 2, and Test 3. Changes in RPE-Load (week-4 vs. week-1) were correlated with changes in performance (r=0.63, p=0.03) and the RPE-Load was correlated with the LALoad (r=0.80, p=0.01). The estimation of the session-RPE training load may be helpful for taper planning of young swimmers. Increasing the difference between the normal and last week of taper training load may facilitate performance improvements. [ABSTRACT FROM AUTHOR]

Purpose. Swimming analysis on up to 200 m events pointed out that the first 15 m plays an important role in the performance result. Hence the hydrodynamic ability to glide under water in a streamline position. Should not be neglected during training, especially in young competitors. Glide in one of five important tips of training .The purpose of this study was to identify Training Program (contains land exercise and water drills. And its effect on the glide performance in (15 m) crawls and breaststrokes in young swimmers Methods. Sample contains (30 young swimmers) dived into two groups (control group) & (experimental group) , each one 15 young swimmers male ( mean ± SD , age 13 ± 1.5 years , height 166 ± 8 cm , body mass 52.3 ± 11.3 kg. Study used tests to measure gliding includes: Starting block and asked to dive and swim foe 15 m crawl CR and 15 m breaststroke (BR) in two different trails. Later subjects underwent a series of hydrodynamic tests such as : diving and gliding under water in a streamline position for 8 m ( DG ) , pushing off from the wall and gliding underwater position 8 m (PG) , pushing off from the wall , gilding and swimming crawl for 12.5 m (PGC) , pushing from the wall , gliding and swimming breaststroke for 12.5 m (PGB) , sculling while floating on the back for 10m (SC) . Time was recorded. Results. There was a statistically significant between the two measures (pre &post) for the experimental group and between the two (post) measures for control and experimental groups. Conclusions. As a result the specific exercise program has been improved performance of gliding through crawl and breaststroke for young swimmers. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: Existing work using dry land exercise-related activities has shown that the careful application of music can lead to a range of benefits that include enhanced affect, lower perceived exertion, greater energy efficiency, and faster time trial performances. The purpose of this study was to assess the psychological, psychophysical, and ergogenic effects of asynchronous music in swimming using a mixed-methods approach. Design: A mixed-model design was employed wherein there was a within-subjects factor (two experimental conditions and a control) and a between-subjects factor (gender). The experimental component of the study was supplemented by qualitative data that were analysed using inductive content analysis. Methods: Twenty six participants (M age = 20.0 years, age range: 18–23 years) underwent a period of habituation with Speedo Aquabeat MP3 players prior to the experimental phase. They were then administered two experimental trials (motivational and oudeterous music at 130 bpm) and a no-music control, during which they engaged in a 200-m freestyle swimming time trial. Results: Participants swam significantly faster when exposed to either music condition relative to control (p = .022, ). Moreover, the music conditions were associated with higher state motivation (p = .016, ) and more dissociative thoughts (p = .014, ). Conclusions: Findings supported the hypothesis that the use of asynchronous music during a high-intensity task can have an ergogenic effect; this was in the order of 2% when averaged out across the two experimental conditions. The use of music, regardless of its motivational qualities, resulted in higher self-reported motivation as well as more dissociative thoughts. [Copyright &y& Elsevier]

In the recent years, Masters swimming movement gained momentum in Romania, as a necessity of health maintaining at adult age by practicing swimming, on the one hand, and as a continuation or a repetition of the competition activity of our country's former high-level swimmers. Grouped in clubs affiliated at the Romanian Swimming and Modern Pentathlon Federation, with its own competition schedule, athletes involved in this movement are doing their best in order to train very seriously. In this paper we will study the effort's dosage and the efficient programming of their activity, the training contain specific means and methods and the cutting edge specific aids, and all together increase efficiency and improves swimming performance. As an evidence are the results obtained by the swimmers from the two big Masters clubs from Romania (Reşiţa 07 and Tribeach Braşov), that include great names of the Romanian swimming: Carmen Bunaciu, Anca Pătrăşcoiu, Ştefan Gherghel, Răzvan Florea, Tudor Ignat, that competed at the World Masters Swimming Championships, which took place in Riccione, between 10-17.06.2012. The titles of world champions and vice champions, along with the top emeritus rankings, prove that this sport can be practiced until old ages, and can bring satisfaction through the results obtained in national and international competitions. [ABSTRACT FROM AUTHOR]

The research is conducted on a sample of 39 woman, top swimmers, participants in the discipline woman 200 meters freestyle stroke swimming, the swimming competitions of the Olympic games held in Sydney in 2000, which are applied and studied 11 relevant biomechanical variables recorded to swimmers. So applying regression analysis determined the impact biomehanical variables presented as predictorial on variables parameter, which is the final result (FRES). By applying factor analysis, showed that the structure of the biomechanical variables in the latent space and the extracted factors are presented as a system of predictorial variables and applying regression analysis determined the impact of variables parameters. Based on the analysis of the obtained results can be found all seven confirmed hypothesis set, which are treated as expected. [ABSTRACT FROM AUTHOR]

Finalist swimmers in the 2nd International Swimming Meeting, which was held in Banja Luka from 16 to 17 April 2011, were related to 100m breast stroke. The result efficiency of the competitors in the mentioned section of A and B finals showed inconsiderable statistical differences. nd The research was conducted on the male competitors of the 2nd International Meeting in Banja Luka. The sample was consisted of 18 competitors who were ranked in the A and B finals. Chronological age of the A final's participants was related to the year of birth from 1990 to 1995, whereas B final's participants year span varied from 1992 to 1997. Sample of variables (measuring instruments) was result efficiency at 100m expressed in stylized form of breast stroke movements. The results were subjected to the descriptive analysis of central tendency measures and to the T-test. The results of the central tendency measures had less numerical value with the A finalists compared to the B finalists. On the other hand, similar results have larger numerical values according to the score boards of the swimming competitions. Sample, consisting of 18 male respondents who were ranked in the A and B finals of the 2nd International Swimming Meeting held on 16 and 17 April 2011, shows inconsiderable statistical significance, but it is still worthy of attention and analysis for the success in swimming; not only in major swimming competitions (World Cups, Olympic Games, Championships, Meetings etc.), but in regional competitions also. [ABSTRACT FROM AUTHOR]

performance in competitive swimming is influenced by the swimmer's figure, by the force and resistance of muscular factors; nevertheless the most important key factors are represented by the swimming techniques including the strokes, the take-off, the turn, touching the wall and the start. Therefore, the shorter the swimming distance, the more important the starting effect. Many start techniques are used in competitive swimming, such as grab start, track start or swing start. The grab start and track start are among the most popular techniques currently used for individual competitions. [ABSTRACT FROM AUTHOR]

The research is conducted on a sample of 39 male, top swimmers, participants in the discipline male 100 meters freestyle stroke swimming, the swimming competitions of the Olympic games held in Sydney in 2000, on which are 11 relevant biomechanical variables were applied, studied and recorded toward the swimmers. The applied regression analysis determined the impact biomechanical variables presented as predictorial on variables parameter, which is the final result (FRES). By applying factor analysis, it has been shown that the structure of the biomechanical variables in the latent space and the extracted factors are presented as a system of predictorial variables. Applied regression analysis has determined the impact of variables parameters. Based on the analysis of the obtained results, which were treated as expected that both isolated varimaks factors have statistically significant partial affect on the outcome toward the criterion result, which were: the specific speed and agility factor and the second was extracted factor response, the frequency, amplitude and efficiency of the strokes. [ABSTRACT FROM AUTHOR]

Analysis of the results of disabled swimmers participating in the Beijing Paralympics showed that in order to advance to the finals in the competition had to swim the time, which at the Athens Paralympics guaranteed a medal, and often even a gold one. This means that to win a medal in Beijing, you had to swim the time close to the world record, and even then success was not always guaranteed. The study analyzed the results of the medalists of individual swimming competitions which were in the program of the Paralympics from 1992 to 2008. Progression of the results was assessed using the formula determining the per cent improvement in results. The analysis revealed an upward trend that could determine the progression. [ABSTRACT FROM AUTHOR]

Copyright of Media4u Magazine is the property of Ing. Jan Chromy, Ph.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Education. Physical Training. Sport / Ugdymas. Kûno kultûra. Sportas is the property of Lithuanian Sports University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The aim of the study was to assess changes in motivation levels in the subjects who were provided with motivational music (independent variable). The additional aim was to establish differences between two study groups in terms of swimming effectiveness. Material/Methods: The employed research method relied on a laboratory experiment. The study included 8 subjects involved in swimming training. They were divided into two groups - control (C) and experimental (E) ones. The study consisted of three trials during which the subjects swam a distance of 50m front crawl with maximum velocity. In the first trial neither of the groups had an independent variable. In trials two and three group C swam the distance listening to white noise. Group E received motivational music of choice (independent variable). Before and after the trials the subjects' motivation was assessed by means of the MOTO scale. Results: The motivation level assessed by means of the MOTO scale revealed no statistically significant differences in the groups. The Mann-Whitney U Test showed no statistically significant differences between the study groups in terms of their times over 50 m. Conclusions: Motivational music which the swimmers received when swimming had no impact on an increased level of the swimmers' motivation and swimming effectiveness. [ABSTRACT FROM AUTHOR]

Abstract: In competitive human swimming the submerged dolphin kick stroke (underwater undulatory swimming) is utilized after dives and turns. The optimal dolphin kick has a balance between minimizing drag and maximizing thrust while also minimizing the physical exertion required of the swimmer. In this study laser scans of athletes are used to provide realistic swimmer geometries in a single anatomical pose. These are rigged and animated to closely match side-on video footage. Smoothed Particle Hydrodynamics (SPH) fluid simulations are performed to evaluate variants of this swimming stroke technique. This computational approach provides full temporal and spatial information about the flow moving around the deforming swimmer model. The effects of changes in ankle flexibility and stroke frequency are investigated through a parametric study. The results suggest that the net streamwise force on the swimmer is relatively insensitive to ankle flexibility but is strongly dependent on kick frequency. [Copyright &y& Elsevier]

Copyright of Timisoara Physical Education & Rehabilitation Journal is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)