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Open access

José María González Ravé, Alejandro Legaz-Arrese, Fernando González-Mohíno, Inmaculada Yustres, Rubén Barragán, Francisco de Asís Fernández, Daniel Juárez and Juan Jaime Arroyo-Toledo

Abstract

This study used a power rack device to evaluate the effects of 2 different approaches to resisted swim training loads on swimming strength and performance. Sixteen male, youth national-level swimmers (mean age, 16.22 ± 2.63 years; body height, 169 ± 10.20 cm; body mass, 61.33 ± 9.90 kg) completed a 6-week specific strength-training program, and were then randomly assigned to one of the two groups: a standard training group (GS, n = 8) and a flat pyramid-loading pattern group (GP, n = 8). Strength and power tests along with specific swimming tests (50-m crawl and 50-m competition-style time trials) were conducted at baseline (pre-test), before the third week (mid-test), and after 6 weeks of intervention (post-test). Isokinetic swim bench tests were conducted to obtain measurements of force production and power, and 1RM tests with the power rack system were conducted to measure the maximum drag load (MDL) and specific swimming power. Following 6 weeks of intervention, the mean MDL increased (p < 0.05) by 13.94%. Scores for the 50-m competition style and 50-m crawl time trials improved by 0.32% and 0.78%, respectively, in the GP; however, those changes were not statistically significant. The GS significantly increased their time in the 50-m competition style by 2.59%, and their isokinetic force production decreased by 14.47% (p < 0.05). The 6-week strength-training program performed with the power rack device in a pyramidal organization was more effective than a standard linear load organization in terms of producing improvements in the MDL; however, it did not produce significant improvements in performance. The use of a strength-training program with a pyramidal organization can be recommended for specific strength-training in young swimmers during a preparatory period. However, in our study, that program did not produce significant changes in 50-m crawl and main competition style performance.

Open access

Biljana Jakovljevic, Sasa Plecevic, Anica Petkovic, Tamara Nikolic Turnic, Isidora Milosavljevic, Kristina Radoman and Ivan Srejovic

Abstract

The investigation was aimed to evaluate the effects of 3-weeks swimming exercise on blood pressure and redox status in high-salt-induced hypertensive rats. Male Wistar albino rats (n=40, 6 weeks old) were divided into 4 groups: 1. hypertensive rats that swam for 3 weeks; 2. sedentary hypertensive control rats; 3. normotensive rats that swam for 3 weeks; 4. sedentary normotensive control rats. Hypertensive animals were on high concentrated sodium (8% NaCl) solution for 4 weeks (period of induction of hypertension). After sacrificing, hearts were isolated and perfused according to Langendorff technique at gradually increased coronary perfusion pressure from 40-120 cmH2O. The oxidative stress markers were determined in coronary venous effluent: the index of lipid peroxidation (measured as TBARS), nitrites (NO2 -), superoxide anion radical (O2 -) and hydrogen peroxide (H2O2). Swimming did not lead to significant changes in levels of TBARS, NO2 -, O2 - in any of compared groups while levels of H2O2 were significantly higher in swimming hypertensive group comparing to swimming normotensive group at coronary perfusion pressure of 80-120 cmH2O. Our results indicate that the short-term swimming start to reduce blood pressure. In addition it seems that this type of swimming duration does not promote cardiac oxidative stress damages.

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.

Open access

Vassilios Thanopoulos, Georgia Rozi, Tomislav Okičić, Milivoj Dopsaj, Bojan Jorgić, Dejan Madić, Saša Veličković, Zoran Milanović, Fani Spanou and Emilios Batis

Differences in the Efficiency Between the Grab and Track Starts for Both Genders in Greek Young Swimmers

The aim of this study was to determine the differences in the kinematic parameters between the grab and track starts and the differences in these two starts between genders. A total of 27 swimmers at the competitive level participated in the study, 13 boys (mean ± SD: age 15.8 ± 0.8 years, body mass 67.7 ± 7.7 kg and body height 178.6 ± 5.7 cm) and 14 girls (mean ± SD: age 16 ± 0.8 years, body mass 59.2 ± 6.6 kg and body height 166.2 ± 6.7 cm). Each swimmer performed three attempts for both start techniques. The best attempt of the grab start and the track start was taken for further analysis. The following kinematic parameters were analysed: flight distance, flight time, flight velocity, entry angle and reaction time. The males had greater numeric values for the results in all kinematic parameters for the grab start compared with the track start, except for flight velocity and entry angle (flight time 0.42 vs. 0.41 s, flight distance 3.21 vs. 3.14 m, flight velocity 7.76 vs. 7.83 m/s, entry angle 44.22 vs. 43.85 degrees and reaction time 0.86 vs. 0.81 s). The females also had greater numeric values for the results in all kinematic parameters for the grab start compared with the track start, except for flight time (flight time 0.38 vs. 0.38 s, flight distance 2.82 vs. 2.73 m, flight velocity 7.47 vs. 7.31 m/s, entry angle 45.18 vs. 44.79 degrees and reaction time 0.88 vs. 0.82 s). These results indicate that the males had significantly better results for flight time and flight distance compared with the females for the grab start (flight time 0.42 vs. 0.38 s, flight distance 3.21 vs. 2.82 m). In the case of the track start, the males had significantly better results for flight distance (3.14 vs. 2.73 m). Exploring the characteristics of the two starts did not lead to any significant kinematic differences. Therefore, a conclusion that demonstrates the superiority of one of the techniques cannot be reached. The coach, together with each swimmer individually, should devote some time to decide after some tests what type of start is better for the body type and general qualifications of the swimmer.

Open access

Krystyna Zatoń and Stefan Szczepan

Abstract

The main objective of the study was to determine the impact of immediate verbal feedback on swimming effectiveness. Swimming effectiveness was expressed in the subjects reaching their objective, i.e., maximum swimming velocity. The study involved 64 subjects divided into two groups (experimental group n=32; control group n=32). Two measurements - initial (pre-test) and final (post-test) - were conducted. The subjects swam a distance of 25 m front crawl at maximum velocity. The experimental groups received immediate verbal feedback focused on stroke lengthening, as a shorter stroke length is regarded as the most common reason behind lower swimming velocity. From this perspective, lengthening the stroke is important due to its relation with mechanics and energetics in all styles of swimming. The control group received no verbal feedback. All tests were recorded via video cameras (50 samples·s-1). The analysis of the kinematic movement parameters (horizontal average swimming velocity over 15m, time achieved over 15m) was carried out by means of the SIMI Reality Motion Systems 2D software. Analysis of variance with repeated measurements with a Tukey’s test demonstrated statistically significant differences (p<0.05) in the tested groups in the case of the kinematic parameters measured in the study. Immediate verbal feedback (IVF) caused an increase of the average horizontal swimming velocity by 2.92% (0.04 m·s-1). Consequently, the average time needed by the swimmers to cover the distance (15m) decreased by 2.94% (0.36s). The results confirmed the effectiveness of the proposed method of teaching and improving the swimming technique using IVF.

Open access

Yuji Matsuda, Yosuke Yamada, Yasushi Ikuta, Teruo Nomura and Shingo Oda

Abstract

The aim of this study was to examine whether the intracyclic velocity variation (IVV) was lower in elite swimmers than in beginner swimmers at various velocities, and whether differences may be related to arm coordination. Seven elite and nine beginner male swimmers swam front crawl at four different swimming velocities (maximal velocity, 75%, 85%, and 95% of maximal swimming velocity). The index of arm coordination (IDC) was calculated as the lag time between the propulsive phases of each arm. IVV was determined from the coefficient of variation of horizontal velocity within one stroke cycle. IVV for elite swimmers was significantly lower (26%) than that for beginner swimmers at all swimming velocities . In contrast, the IDC was similar between elite and beginner swimmers. These data suggest that IVV is a strong predictor of the skill level for front crawl, and that elite swimmers have techniques to decrease IVV. However, the IDC does not contribute to IVV differences between elite and beginner swimmers.

Open access

Nuno Batalha, Sónia Dias, Daniel A. Marinho and José A. Parraca

Abstract

The continuous execution of swimming techniques, supported mainly by the upper limbs, may cause shoulder rotator muscle imbalances, which leads to injuries. The aim of this study was to evaluate and compare the effects of two training programs on strength, balance and endurance of shoulder rotator cuff muscles in youth swimmers. Twenty-five male swimmers were evaluated and randomly divided into two groups – the land group (n = 13), which conducted a conventional dry-land training program with elastic bands, and the water group (n = 12), which conducted a water resistance program. In both groups, the level of strength of the shoulder rotators was evaluated with an isokinetic dynamometer on two occasions (baseline and after 10 weeks) using two protocols: i) three repetitions at 60o/s; ii) twenty repetitions at 180o/s. The land group significantly increased the unilateral ratios compared to the water group. The land group also decreased the external rotator levels of muscular fatigue. The dry-land training program conducted proved to be more effective than the one conducted in the water, allowing to reduce the muscle imbalance and to decrease muscle fatigue.

Open access

Beat Knechtle, Caio Victor de Sousa, Herbert Gustavo Simões, Thomas Rosemann and Pantelis Theodoros Nikolaidis

Abstract

The aim of this study was to examine the effects of the performance level and race distance on pacing in ultra-triathlons (Double, Triple, Quintuple and Deca), wherein pacing is defined as the relative time (%) spent in each discipline (swimming, cycling and running). All finishers (n = 3,622) of Double, Triple, Quintuple and Deca Iron ultra-triathlons between 1985 and 2016 were analysed and classified into quartile groups (Q1, Q2, Q3 and Q4) with Q1 being the fastest and Q4 the slowest. Performance of all non-finishers (n = 1,000) during the same period was also examined. Triple and Quintuple triathlons (24.4%) produced the highest rate of non-finishers, and Deca Iron ultra-triathlons produced the lowest rate (18.0%) (χ2 = 12.1, p = 0.007, φC = 0.05). For the relative swimming and cycling times (%), Deca triathletes (6.7 ± 1.5% and 48.8 ± 4.9%, respectively) proved the fastest and Double (9.2 ± 1.6% and 49.6 ± 3.6%) Iron ultra-triathletes were the slowest (p < 0.008) with Q4 being the fastest group (8.3 ± 1.6% and 48.8 ± 4.3%) and Q1 the slowest one (9.5 ± 1.5% and 50.9 ± 3.0%) (p < 0.001). In running, Double triathletes were relatively the fastest (41.2 ± 4.0%) and Deca (44.5 ± 5.4%) Iron ultra-triathletes the slowest (p < 0.001) with Q1 being the fastest (39.6 ± 3.3%) and Q4 the slowest group (42.9 ± 4.7%) (p < 0.001). Based on these findings, it was concluded that the fastest ultra-triathletes spent relatively more time swimming and cycling and less time running, highlighting the importance of the role of the latter discipline for the overall ultra-triathlon performance. Furthermore, coaches and ultra-triathletes should be aware of differences in pacing between Double, Triple, Quintuple and Deca Iron triathlons.

Open access

Jorge Morais, Mário Costa, Erik Mejias, Daniel Marinho, António Silva and Tiago Barbosa

Morphometric Study for Estimation and Validation of Trunk Transverse Surface Area To Assess Human Drag Force on Water

The aim of this study was to compute and validate estimation equations for the trunk transverse surface area (TTSA) to be used in assessing the swimmer's drag force in both genders. One group of 133 swimmers (56 females, 77 males) was used to compute the estimation equations and another group of 131 swimmers (56 females, 75 males) was used for its validations. Swimmers were photographed in the transverse plane from above, on land, in the upright and hydrodynamic position. The TTSA was measured from the swimmer's photo with specific software. Also measured was the height, body mass, biacromial diameter, chest sagital diameter (CSD) and the chest perimeter (CP). With the first group of swimmers, it was computed the TTSA estimation equations based on stepwise multiple regression models from the selected anthropometrical variables. For males TTSA=6.662*CP+17.019*CSD-210.708 (R2=0.32; Ra 2=0.30; P<0.01) and for females TTSA=7.002*CP+15.382*CSD-255.70 (R2=0.34; Ra 2=0.31; P<0.01). For both genders there were no significant differences between assessed and estimated mean TTSA. Coefficients of determination for the linear regression models between assessed and estimated TTSA were R2=0.39 for males and R2=0.55 for females. More than 80% of the plots were within the 95% interval confidence for the Bland-Altman analysis in both genders.