Front Crawl Intracyclic Velocity Variation Of The Hip In Swimmers With Down Syndrome

2009 ◽  
Vol 41 ◽  
pp. 387
Author(s):  
Pedro Figueiredo ◽  
Inês Aleixo ◽  
António Castro ◽  
João Brito ◽  
Rui Corredeira ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Velocity Variation ◽  
Front Crawl

Intracyclic Velocity Variation and Arm Coordination Assessment in Swimmers With Down Syndrome

2013 ◽  
Vol 30 (1) ◽  
pp. 70-84 ◽  
Author(s):  
Inês Marques-Aleixo ◽  
Ana Querido ◽  
Pedro Figueiredo ◽  
João Paulo Vilas-Boas ◽  
Rui Corredeira ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Repeated Measures ◽  
Swimming Performance ◽  
Movement Analysis ◽  
Velocity Variation ◽  
Swimming Velocity ◽  
Front Crawl ◽  
Catch Up ◽  
Arm Coordination ◽  
Nonpreferred Side

This study examined the differences in intracycle velocity variation and arm coordination in front crawl in swimmers with Down syndrome in three breathing conditions. International swimmers with Down syndrome (N = 16) performed 3 × 20 m front crawl at 50 m race speed: without breathing, breathing to the preferred side, and breathing to the nonpreferred side. A two dimensional video movement analysis was performed using the APASystem. Breathing conditions were compared using Repeated Measures ANOVA. Swimming velocity was higher without breathing and intracyclic velocity variation was higher while breathing. Swimmers tended to a catch up arm coordination mode for both breathing conditions and a superposition mode when not breathing. These data reflect arm coordination compromising swimming performance, particularly when comparing with non disabled swimmers in literature. The physical and perhaps cognitive impairment associated with Down syndrome may result in a disadvantage in both propulsion and drag, more evident when breathing.

scholarly journals Monitoring Master Swimmers’ Performance and Active Drag Evolution along a Training Mesocycle

2021 ◽  
Vol 18 (7) ◽  
pp. 3569
Author(s):  
Henrique P. Neiva ◽  
Ricardo J. Fernandes ◽  
Ricardo Cardoso ◽  
Daniel A. Marinho ◽  
J. Arturo Abraldes
Keyword(s):  
Aerobic Training ◽  
Training Period ◽  
Velocity Variation ◽  
Hydrodynamic Drag ◽  
Swimming Training ◽  
Front Crawl ◽  
Maximal Intensity ◽  
Before And After ◽  
Active Drag

This study aimed to analyze the effects of a swimming training mesocycle in master swimmers’ performance and active drag. Twenty-two 39.87 ± 6.10 year-old master swimmers performed a 25 m front crawl at maximal intensity before and after a typical four-week training mesocycle. Maximum, mean and minimum speeds, speed decrease and hip horizontal intra-cyclic velocity variation were assessed using an electromechanical speedometer, and the active drag and power to overcome drag were determined using the measuring active drag system. Maximum, mean and minimum front crawl speeds improved from pre- to post-training (mean ± 95% CI: 3.1 ± 2.8%, p = 0.04; 2.9 ± 1.6%, p = 0.01; and 4.6 ± 3.1%, p = 0.01; respectively) and the speed decrease along the 25 m test lowered after the training period (82.5 ± 76.3%, p = 0.01). The training mesocycle caused a reduction in the active drag at speeds corresponding to 70% (5.0 ± 3.9%), 80% (5.6 ± 4.0%), and 90% (5.9 ± 4.0%), but not at 100% (5.9 ± 6.7%), of the swimmers’ maximal exertions in the 25 m test. These results showed that four weeks of predominantly aerobic training could improve master swimmers’ performance and reduce their hydrodynamic drag while swimming mainly at submaximal speeds.

scholarly journals The 400-m Front Crawl Test: Energetic and 3D Kinematical Analyses

2019 ◽  
Vol 41 (01) ◽  
pp. 21-26
Author(s):  
Ricardo de Assis Correia ◽  
Wellington Gomes Feitosa ◽  
Pedro Figueiredo ◽  
Marcelo Papoti ◽  
Flávio Antonio de Souza Castro
Keyword(s):  
Oxygen Consumption ◽  
Test Performance ◽  
Lactate Concentration ◽  
Three Dimensional ◽  
Velocity Variation ◽  
Centre Of Mass ◽  
Front Crawl ◽  
Competition Level ◽  
The Mean ◽  
Linear Regressions

AbstractThe aim of the study was to verify the relative contributions of energetic and kinematic parameters to the performance in 400-m front crawl test. Fourteen middle-distance swimmers participated in the study. Oxygen consumption was measured directly and blood samples were collected to assay lactate concentration. Both oxygen consumption and lactate concentration were used to calculate the: (i) overall energy expenditure, (ii) anaerobic (alactic and lactic) and (iii) aerobic contributions. The mean centre of mass speed and intracycle velocity variation were determined through three-dimensional kinematic analysis. Mean completion time was 315.64±26.91s. Energetic contributions were as follows: 6.1±0.28% from alactic anaerobic metabolism, 5.9±0.63% from anaerobic lactic and 87.8±0.88% from aerobic. Mean intracycle velocity variation was 0.14±0.03. The results indicated that performance of 400-m test relies predominantly on aerobic power. Parameters such as lactate, mean speed, anaerobic lactic and alactic (kW) correlated with performance of 400-m test (p <0.05). Multiple linear regressions indicated that mean centre of mass speed and anaerobic alactic (kW) determined the 400-m test performance (R2=0.92). Even though the T400 is characterized by aerobic metabolism, the anaerobic alactic component cannot be negligible at this competition level.

Intracyclic Variation of Force and Swimming Performance

2018 ◽  
Vol 13 (7) ◽  
pp. 897-902 ◽  
Author(s):  
Pedro G. Morouço ◽  
Tiago M. Barbosa ◽  
Raul Arellano ◽  
João P. Vilas-Boas
Keyword(s):  
Swimming Performance ◽  
Time Trial ◽  
Velocity Variation ◽  
Swimming Velocity ◽  
Stroke Rate ◽  
Free Swimming ◽  
Front Crawl ◽  
Continuous Application ◽  
High Level ◽  
Maximal Effort

Context: In front-crawl swimming, the upper limbs perform alternating movements with the aim of achieving a continuous application of force in the water, leading to lower intracyclic velocity variation (dv). This parameter has been identified as a crucial criterion for swimmers’ evaluation. Purpose: To examine the assessment of intracyclic force variation (dF) and to analyze its relationship with dv and swimming performance. Methods: A total of 22 high-level male swimmers performed a maximal-effort 50-m front-crawl time trial and a 30-s maximal-effort fully tethered swimming test, which were randomly assigned. Instantaneous velocity was obtained by a speedometer and force by a strain-gauge system. Results: Similarity was observed between the tests, with dF attaining much higher magnitudes than dv (P < .001; d = 8.89). There were no differences in stroke rate or in physiological responses between tethered and free swimming, with a high level of agreement for the stroke rate and blood lactate increase. Swimming velocity presented a strong negative linear relationship with dF (r = −.826, P < .001) and a moderate negative nonlinear relationship with dv (r = .734, P < .01). With the addition of the maximum impulse to dF, multiple-regression analysis explained 83% of the free-swimming performance. Conclusions: Assessing dF is a promising approach for evaluating a swimmer’s performance. From the experiments, this new parameter showed that swimmers with higher dF also present higher dv, leading to a decrease in performance.

Assessment of Fatigue Thresholds in 50-m All-Out Swimming

2014 ◽  
Vol 9 (6) ◽  
pp. 959-965 ◽  
Author(s):  
Susana M. Soares ◽  
Ricardo J. Fernandes ◽  
J. Leandro Machado ◽  
José A. Maia ◽  
Daniel J. Daly ◽  
...  
Keyword(s):  
Fatigue Threshold ◽  
Velocity Variation ◽  
Time Interval ◽  
Stroke Index ◽  
Time Intervals ◽  
Front Crawl ◽  
Mean Velocity ◽  
Individual Level ◽  
Variation Patterns ◽  
The Mean

Context:It is essential to determine swimmers’ anaerobic potential and better plan training, understanding physiological effects of the fatigue.Purpose:To study changes in the characteristics of the intracyclic velocity variation during an all-out 50-m swim and to observe differences in speed and stroking parameters between these changes.Methods:28 competitive swimmers performed a 50-m front-crawl all-out test while attached to a speedometer. The velocity–time (v[t]) curve off all stroke cycles was analyzed per individual using a routine that included a wavelet procedure, allowing the determination of the fatigue thresholds that divide effort in time intervals.Results:One or 2 fatigue thresholds were observed at individual level on the v(t) curve. In males, when 1 fatigue threshold was identified, the mean velocity and the stroke index dropped (P < .05) in the second time interval (1.7 ± 0.0 vs 1.6 ± 0.0 m/s and 3.0 ± 0.2 vs 2.8 ± 0.3 m/s, respectively). When 2 fatigue thresholds were identified, the mean velocity of the first time interval was higher than that of the third time interval (P < .05), for both male (1.7 ± 0.0 vs 1.6 ± 0.1 m/s) and female (1.5 ± 0.1 vs 1.3 ± 0.1 m/s) swimmers.Conclusion:One or 2 fatigue thresholds were found in the intracyclic velocity-variation patterns. Concurrently, changes in velocity and stroke parameters were also observed between time intervals. This information could allow coaches to obtain new insights into delaying the degenerative effects of fatigue and maintain stable stroke-cycle characteristics over a 50-m event.

scholarly journals Kinematic Variables of Disabled Swimmers and Their Correlation With the International Paralympic Committee Classification

Motor Control ◽  
2021 ◽  
pp. 1-12
Author(s):  
Karini Borges dos Santos ◽  
Paulo Cesar Barauce Bento ◽  
Carl Payton ◽  
André Luiz Felix Rodacki
Keyword(s):  
Velocity Variation ◽  
Swimming Velocity ◽  
Stroke Rate ◽  
Functional Classification ◽  
Crucial Point ◽  
Front Crawl ◽  
Stroke Length ◽  
Underwater Cameras ◽  
Current Classification ◽  
Phase Coordination

This study described the kinematic variables of disabled swimmers’ performance and correlated them with their functional classification. Twenty-one impaired swimmers (S5–S10) performed 50-m maximum front-crawl swimming while being recorded by four underwater cameras. Swimming velocity, stroke rate, stroke length, intracycle velocity variation, stroke dimensions, hand velocity, and coordination index were analyzed. Kendall rank was used to correlate stroke parameters and functional classification with p < .05. Swimming velocity, stroke length, and submerged phase were positively correlated with the para swimmers functional classification (.61, .50, and .41; p < .05, respectively), while stroke rate, velocity hand for each phase, coordination index, and intracyclic velocity variation were not (τ between −.11 and .45; p > .05). Thus, some objective kinematic variables of the impaired swimmers help to support current classification. Improving hand velocity seems to be a crucial point to be improved among disabled swimmers.

A Practical Estimation Method for Center of Mass Velocity in Swimming Direction During Front Crawl Swimming

2018 ◽  
Vol 34 (4) ◽  
pp. 342-347 ◽  
Author(s):  
Yuji Matsuda ◽  
Yoshihisa Sakurai ◽  
Keita Akashi ◽  
Yasuyuki Kubo
Keyword(s):  
Swimming Performance ◽  
Center Of Mass ◽  
Estimation Method ◽  
Practical Method ◽  
Velocity Estimation ◽  
Estimation Methods ◽  
Velocity Variation ◽  
Front Crawl ◽  
Swimming Direction ◽  
Underwater Cameras

Center of mass (CoM) velocity variation in swimming direction is related to swimming performance and efficiency. However, it is difficult to calculate the CoM velocity during swimming. Therefore, we aimed to establish a practical estimation method for the CoM velocity in swimming direction during front crawl swimming with underwater cameras. Ten swimmers were recorded during front crawl swimming (25 m, maximal effort) using a motion capture system with 18 underwater and 9 land cameras. Three CoM velocity estimation methods were constructed (single-hip velocity, both-hips velocity, and both-hips velocity with simulated arm velocity correction). Each model was validated against the actual CoM velocity. The difference between the single-hip velocity and the actual CoM velocity in swimming direction was significantly larger compared with that of the other 2 models. Furthermore, the accuracy of CoM velocity estimation was increased when both-hips velocity was corrected using the simulated arm velocity. The method allowed estimation of the CoM velocity with only 2 underwater cameras with a maximal difference of 0.06 m·s−1. This study established a novel and practical method for the estimation of the CoM velocity in swimming direction during front crawl swimming.

scholarly journals The Influence of the Frontal Surface Area and Swim Velocity Variation in Front Crawl Active Drag

2020 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Jorge E. Morais ◽  
Ross H. Sanders ◽  
Christopher Papic ◽  
Tiago M. Barbosa ◽  
Daniel A. Marinho
Keyword(s):  
Surface Area ◽  
Velocity Variation ◽  
Front Crawl ◽  
Frontal Surface ◽  
Active Drag

scholarly journals Interplay of Biomechanical, Energetic, Coordinative, and Muscular Factors in a 200 m Front Crawl Swim

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Pedro Figueiredo ◽  
David R. Pendergast ◽  
João Paulo Vilas-Boas ◽  
Ricardo J. Fernandes
Keyword(s):  
Linear Regression Analysis ◽  
Muscular Activity ◽  
Multiple Linear Regression Analysis ◽  
Total Energy Expenditure ◽  
Velocity Variation ◽  
Front Crawl ◽  
Stroke Length ◽  
Task Constraints ◽  
Relative Contribution ◽  
Propelling Efficiency

This study aimed to determine the relative contribution of selected biomechanical, energetic, coordinative, and muscular factors for the 200 m front crawl and each of its four laps. Ten swimmers performed a 200 m front crawl swim, as well as 50, 100, and 150 m at the 200 m pace. Biomechanical, energetic, coordinative, and muscular factors were assessed during the 200 m swim. Multiple linear regression analysis was used to identify the weight of the factors to the performance. For each lap, the contributions to the 200 m performance were 17.6, 21.1, 18.4, and 7.6% for stroke length, 16.1, 18.7, 32.1, and 3.2% for stroke rate, 11.2, 13.2, 6.8, and 5.7% for intracycle velocity variation inx, 9.7, 7.5, 1.3, and 5.4% for intracycle velocity variation iny, 17.8, 10.5, 2.0, and 6.4% for propelling efficiency, 4.5, 5.8, 10.9, and 23.7% for total energy expenditure, 10.1, 5.1, 8.3, and 23.7% for interarm coordination, 9.0, 6.2, 8.5, and 5.5% for muscular activity amplitude, and 3.9, 11.9, 11.8, and 18.7% for muscular frequency). The relative contribution of the factors was closely related to the task constraints, especially fatigue, as the major changes occurred from the first to the last lap.

Front Crawl Swimming In Down Syndrome

2014 ◽  
Vol 46 ◽  
pp. 529
Author(s):  
Giampiero Merati ◽  
Arsenio Veisteinas ◽  
Stefano Nurra ◽  
Claudio Ciapparelli ◽  
Cecilia Belletti ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Front Crawl
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