Кейлъб Дресел – най-бързото плуване в историята

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Цифри и анализи – как го правят най-добрите
Плувният свят наскоро бе шокиран от двете невероятни изпълнения на 50 и 100 ярда свободен стил на Кейлъб Дресел.
В публикацията на https://blogs.ugr.es/aquaticslab/ се прави анализ на плуването на 50 ярда в детайли и след това се симулира резултата му на 50 -метров басейн.
Подробният анализ позволява на треньорите и плувците да открият нови методи за ефективност и да определят точни цели на тренировките.
Малките времеви разлики между първата и втората дължина отварят почти негативен сплит на състезателното темпо. / pluvane.net

The fastest swim in the history: 50y Caeleb Dressel Analysis

 

Raúl Arellano

Full Professor. Physical Education and Sport Department. Faculty of Sport Sciences. University of Granada

Introduction:

The World of Swimming has been shocked by two incredible performances in 50y and 100y freestyle, being the main character Caeleb Dressel. His previous performances were pointing us in that direction and they finally materialised!

This post will try to analyse the first event in detail and afterward we will simulate his result in 50m short course.

 

Methods and limitations:

The data were collected from a high-definition video (HD: 1280 x 720, f = 29.97 Hz, H264) provided by Big Ten network. The lanes were used as references to this type of analysis, being coloured in blue and white. In both sides of the swimming pool two turning areas were coloured in blue with a 5 yards length (4.572m). Two specific 15m marks are included in the lane to limit the emersion distance. Therefore, the 25y pool has a 15y space (13.71m) between the turns areas. This space is marked in the lane by 20.5 groups of four lane buoys (four in white and four in blue). Thus, the space of each four buoys segment is about 0.365y (0.334m). The distance 25y is equivalent to 22.86m, 50m is equivalent to 45.72 and 100y is equivalent to 91.44m. An additional source of error has to be considered when times of the underwater displacements are collected. They are approximate, but our experience on these analyses (from Barcelona-92 Olympic Games) can guaranty a good accuracy.

A proprietary data base allowed us to collect each event time code and to include it, in the specific field of the data base, to perform the calculation of the race analysis variables. The official results are included in the analysis and combined with the times collected from the video analysis. Both event times were synchronized thanks to the starting lights located under each starting block.

These events included many unofficial world records as the fastest start or the fastest turn in an official competition. Not only the race is extraordinary also their technique components.

 

Results:

Initial data from the start is included: hands leaving the block, back leg leaving the back support and finally front leg leaving the block (collected from the official results as “reaction time” and additional validity check as different official times). All these data are included in the Table 1.

Two versions of the results are included: results based on yards references as they were explained in the methods sections and results measured in meters to compare with previous results of international performances in meters. The Table 2 includes these results.

Dressel was almost the last swimmer to touch, with the hands, the water surface after the start dive (1.03s) while he arrived to the 5m distance in aproximate 1.33s and simultaneously with the feet entry in the water, a common detail in the top-level swimmers. He was emerging more than half of meter in front of the nearest contender and covered an underwater distance of 12.90m after six dolphin kicks. This advantage was increased after turning, he covered about 11.20m and performed 6/7 kicks. His undulatory technique was linked with the first two emersion arm strokes making simultaneously the dolphin kick instead of the flutter kick, similar to M. Phelps emersion technique.

 

Table 1: Performance results 50y freestyle Caeleb Dressel.

Variable Time (s)
HLB 0.43
KLB 0.51
RT* 0.62
WHT 1.03
T 15m 4.84
T 20y 6.21
T 25y* 8.48
T 25y + 15m 14.40
T 45y 15.78
T 50y* 17.63

* Provided by the official results.

 

Table 2: Performance results 50y freestyle Caeleb Dressel adapted to distances measured in meters.

Variable Time (s)
T 5m 1.33
T 10m 2.90
T 15m 4.84
T 25y – 5m 6.10
T 25y* 8.48
T 25y + 10m 11.98
T 25y + 15m 14.40
T 50y – 5m 15.59
T 50y* 17.63

* Provided by the official results.

 

 

Table 3: Cyclic variables, emersion distance, number of underwater kicks and number of strokes by lap.

Variables Results
First Emersion (m) 12.90
Emersion T1 (s) 3.97
2nd Emersion (m) 11.20
Emersion T2 (s) 3.93
Underwater Kicks 1 6
Underwater Kicks 2 6 or 7
Number of strokes 1st lap 8
Number of strokes 2nd lap 11
Time between the last stroke and the feet touching the wall 0.91
Stroke Frequency (cyc/min)1 70
Stroke Frequency (cyc/min)2 63
Stroke length (m) 1 2.05
Stroke length (m) 1 2.24
Stroke Index 1 4.91
Stroke Index 2 5.32

+ Extended explanation of all the variables can be found in the references listed at the end.

 

The results provided in the tables 1, 2 and 3, will allow us to simulate a 50m short course performance. The procedure is to add the known times: 15m start time, 5+15m turning time, 5m finishing time, and the distances between them in the first lap (between 15m and 20m) and (between 40m and 45m) and to assume that the average velocity is similar to the analysed event (2.86 instead the 5m described). These 2.14m of difference on each lap are the extra swim distance difference between both events and the corresponding gap in the calculations.

 

Table 4: Simulated 50m short course Caerel Dressel performance

Variable Time (s)
T 10m 2.90
T 15m 4.84
T 20m 6.93
T 25m 9.31
T 35m 15.23
T 40m 17.33
T 50m 19.37

 

Table 4 shows the calculated 50m short course time. The application of a swim times calculator converts the 50y 17.63s time to 50m 19.40 short course time, while our prediction based on race analysis data results 19.37 a very narrow difference but now we include all the race splits. In this case the split change between the first and second lap is 0.76s while in the 50y event was 0.67s

 

Discussion:

Just a couple of comments about previous well-known performances. At the Olympics Games of Barcelona Alex Popov obtained a starting time of 3.33s (10m) (Arellano, Brown, Cappaert & Nelson, 1994), in this case Dressel performed a 2.90s time. A time reduction of 0.43s in the first 10m means a lot of changes in this period of time: new starting blocks and their corresponding changes in the start technique, new swimsuits, more distance underwater and a probable different approach to train the leg power required in this short distance. More recent results as the 50m short course record of Florent Manadou included a 10m time about 3s, something similar to the recorded by Dressel, while the time at 15m was 5+s to Manadou and 4,84 to Dressel. The evolution is clear and a higher velocity at the beginning allows a better transition to the stroking phase where arm power will be applied at the maximal level. The Manadou Dec, 2014 record, was performed with a 25m time about 9.7 and a 50m time of 20.26, whiel the predicted times for Dressel have been calculated as 9.31 and 19.37 a dramatic improvement.

 

Conclusions:

The detailed analysis will allow to the coaches and swimmers to stablish new performance targets and clear training objectives. The race components results can orientate, in more detail, which will be in the near future, the race needs for top-level freestyle male 50m swimmers. It is particularly relevant, the narrow time difference between the first and second lap opening an almost negative race pace paradigm in this short event.

 

Funding:

This project DEP 2014-59707-P “SWIM: Specific Water Innovative Measurements applied to the development of International Swimmers in Short Swimming Events (50 and 100m) has been financed by the Spanish Ministery of Economy, Industry and Competitiveness [Spanish Agency of Research] and European Regional Development Fund (ERDF).

 

References:

Arellano, R., Brown, P., Cappaert, J., & Nelson, R. C. (1994). Analysis of 50-M, 100-M, and 200-M Freestyle Swimmers at the 1992 Olympic Games. Journal of Applied Biomechanics, 10(2), 189-199.

Morais, J. E., Marinho, D. A., Arellano, R., & Barbosa, T. M. (2018). Start and turn performances of elite sprinters at the 2016 European Championships in swimming. Sports Biomechanics, 1-15. doi:10.1080/14763141.2018.1435713

 

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