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Open access

Mário J. Costa, Govindasamy Balasekaran, J. Paulo Vilas-Boas and Tiago M. Barbosa

Abstract

The purpose of this systematic review was to summarize longitudinal studies on swimming physiology and get implications for daily practice. A computerized search of databases according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (i) present two testing points; (ii) on swimming physiology; (iii) using adult elite swimmers; (iv) no case-studies or with small sample sizes. Two independent reviewers used a checklist to assess the methodological quality of the studies. Thirty-four studies selected for analysis were gathered into five main categories: blood composition (n=7), endocrine secretion (n=11), muscle biochemistry (n=7), cardiovascular response (n=8) and the energetic profile (n=14). The mean quality index was 10.58 ± 2.19 points demonstrating an almost perfect agreement between reviewers (K = 0.93). It can be concluded that the mixed findings in the literature are due to the diversity of the experimental designs. Micro variables obtained at the cellular or molecular level are sensitive measures and demonstrate overtraining signs and health symptoms. The improvement of macro variables (i.e. main physiological systems) is limited and may depend on the athletes’ training background and experience.

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

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

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

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

Paulo Simões, José Vasconcelos-Raposo, António Silva and Helder Fernandes

Effects of a Process-Oriented Goal Setting Model on Swimmer's Performance

The aim of this work was to study the impact of the implementation of a mental training program on swimmers' chronometric performance, with national and international Portuguese swimmers, based on the goal setting model proposed by Vasconcelos-Raposo (2001). This longitudinal study comprised a sample of nine swimmers (four male and five female) aged between fourteen and twenty, with five to eleven years of competitive experience. All swimmers were submitted to an evaluation system during two years. The first season involved the implementation of the goal setting model, and the second season was only evaluation, totaling seven assessments over the two years. The main results showed a significant improvement in chronometric performance during psychological intervention, followed by a reduction in swimmers' performance in the second season, when there was no interference from the investigators (follow-up).

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

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

Amanda Casey, Colin Boyd, Sasho MacKenzie and Roy Rasmussen

Dual-Energy X-Ray Absorptiometry to Measure the Effects of a Thirteen-Week Moderate to Vigorous Aquatic Exercise and Nutritional Education Intervention on Percent Body Fat in Adults with Intellectual Disabilities from Group Home Settings

People with intellectual disability are more likely to be obese and extremely obese than people without intellectual disability with rates remaining elevated among adults, women and individuals living in community settings. Dual-energy X-ray absorptiometry measured the effects of a 13-week aquatic exercise and nutrition intervention on percent body fat in eight adults with intellectual disabilities (aged 41.0 ± 13.7 yrs) of varying fat levels (15%-39%) from two group homes. A moderate to vigorous aquatic exercise program lasted for the duration of 13 weeks with three, one-hour sessions held at a 25m pool each week. Nutritional assistants educated participants as to the importance of food choice and portion size. A two-tailed Wilcoxon matched-pairs signed-ranks test determined the impact of the combined intervention on body fat percentage and BMI at pre and post test. Median body fat percentage (0.8 %) and BMI (0.3 kg/m2) decreased following the exercise intervention, but neither were statistically significant, p = .11 and p = .55, respectively. The combined intervention was ineffective at reducing percent body fat in adults with intellectual disability according to dual-energy X-ray absorptiometry. These results are in agreement with findings from exercise alone interventions and suggest that more stringent nutritional guidelines are needed for this population and especially for individuals living in group home settings. The study did show that adults with intellectual disability may participate in moderate to vigorous physical activity when given the opportunity.

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.