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1

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

100%

Thanopoulos V., Rozi G., Okičić T., Dopsaj M., Jorgić B., Madić D., Veličković S., Milanović Z., Spanou F., Batis E.

Journal of Human Kinetics

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2012

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vol. 32

43-51

EN

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.

2

Kinematic Analysis of Canoe Stroke and its Changes During Different Types of Paddling Pace - Case Study

100%

Zahálka F., Malý T., Malá L., Doktor M., Větrovský J.

Journal of Human Kinetics

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2011

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vol. 29

25-33

EN

The aim of the study was to describe and evaluate movements of an elite canoeist when different paddling paces are applied. One of the tasks consisted of finding differences in time-space characteristics of selected markers in the referencing system canoeist's body - canoe. 3D kinematic analysis was used for identification and comparison of selected parameters. The study confirmed that an elite canoeist has a high level of movement similarity in all types of stroke rates; differences were mainly found in time sequence of applied strokes. To evaluate properly the racing stroke rate, start, flying start, 200m pace, 500m pace, and 1000m pace were chosen. One of the evaluated parameters was the boat velocity that was 2.1-4.5 ms-1 at start, 3.2-5.2 ms-1 at flying start, 3.9-6.1 ms-1 at 200m pace, 3.9-5.9 ms-1 at 500m pace and 3.0-5.4 ms-1 at 1000m pace. Vertical change of the position of the right hand was 0.77 m at start, 0.73 m at flying start, 0.87 at 200m pace, 0.89 at 500m pace and 0.81 m at 1000m pace.

3

Analysis of Match Performance of Full-backs from Selected European Soccer Leagues

100%

Konefał M., Chmura P., Andrzejewski M., Pukszta D., Chmura J.

Central European Journal of Sport Sciences and Medicine

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2015

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vol. 11

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issue 3

45-53

EN

The aim of the present study was the analysis of match activities of full-backs from selected European national soccer leagues. The study sample comprised 30 full-backs playing in the autumn round of the 2014/15 season from five European national top-tier leagues: English Premier League, Spanish Primera Division, German Bundesliga, Russian Priemjer Liga and Italian Serie A. The performance of full-backs (left-back and right-back) from each selected team was analyzed using a professional match analysis system OptaPro which tracks every possible type of ball touch and on the ball action in match covered by a rigid set of definitions. The data for analysis included the total number of passes, total number of crosses, and total number of ball touches performed by the fullbacks in three zones of the pitch: attack, midfield and defense. The study results showed that the full-backs from the Spanish Primera Division executed the highest number of passes and crosses as well as ball touches in the attack zone. They also performed the lowest number of passes in the midfield and defense zones, in which the highest percentage of passes was achieved by the full-backs from the German league teams. The study indicates that in modern soccer defenders must possess a high level of offensive skills that can be necessary in the last stage of a team’s attack.

4

Validity of Mechanical Power Output Measurement at Bench Press Exercise

100%

Jandaĉka D., Vaverka F.

Journal of Human Kinetics

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2009

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vol. 21

33-40

EN

In sport training and rehabilitation practice, it is usual to use methods of mechanical muscle power output measurement, which are based mainly on indirect force measurement. The aim of this study was to verify the validity of indirect measurement for mechanical muscle power output with bench press exercise. As a criterion of validity, we selected a combination of kinematic and dynamic analyses. Ten men participated in this study. Average age of tested subjects was 28.0 ± 3.4 years. At mechanical power output measurement, these subjects lifted at maximum possible speed loads of 18, 26.5, 39.2 and 47.7 kg. Validity of mechanical power output measurement by means of a method using indirect force measurement was estimated using Spearmen's Correlation Coefficient. Factual significance of differences in average values of power output, force and velocity, measured by a method using indirect force measurement, in comparison to the selected criterion, was evaluated by means of effect of size. Power output measurement method using indirect force measurement showed lower values of force in relation to the criterion in the whole scope of selected loads. Velocity values in the whole scope of selected loads did not show any significant difference between the criterion and the verified method. The mechanical muscle power output measured by the method using indirect force measurement is lower in relation to the criterion, especially in the low scope of loads, where also validity rate was low (R = 0.5).

5

Kinematic Structure at the Early Flight Position in Ski Jumping

100%

Vodičar J., Čoh M., Jošt B.

Journal of Human Kinetics

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2012

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vol. 35

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issue 1

35-45

EN

The purpose of our research was to establish the variability of correlation between the length of the jumps and selected multi-item kinematic variables (n=9) in the early flight phase technique of ski jumping. This study was conducted on a sample of elite Slovenian ski jumpers (N=29) who participated in the experiment on a jumping hill in Hinterzarten, Germany (HS95m) on the 20th of August, 2008. The highest and most significant correlations (p=0.01) with the length of the ski jump were found in the multi-item variable height of flying, which was also expressed with the highest level of stability of the explained total variance (TV) on the first factor (TV=69.13%). The most important characteristic of the aerodynamic aspect of early flight was the variable angle between the body chord and the horizontal axis with significantly high correlations (p<0.05). The stability of that aerodynamic factor was very high (TV=65.04%). The results were essentially similar for the multi-item variable angle between left leg and the horizontal axis (TV=61.88%). The rest of the multi-item kinematic variables did not have significant correlations with the multi-item variable length of jump. Only two more variables, the angle between the upper body and the horizontal plane (TV=53.69%), and the angle between left ski and left leg (TV=50.13%), had an explained common variance on the first factor greater than 50% of total variance. The results indicated that some kinematic parameters of ski jumping early flight technique were more important for success considering the length of the jump.

6

A Kinematics Analysis Of Three Best 100 M Performances Ever

100%

Krzysztof M., Mero A.

Journal of Human Kinetics

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2013

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vol. 36

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issue 1

149-160

EN

The purpose of this investigation was to compare and determine the relevance of the morphological characteristics and variability of running speed parameters (stride length and stride frequency) between Usain Bolt’s three best 100 m performances. Based on this, an attempt was made to define which factors determine the performance of Usain Bolt's sprint and, therefore, distinguish him from other sprinters. We analyzed the previous world record of 9.69 s set in the 2008 Beijing Olympics, the current record of 9.58 s set in the 2009 Berlin World Championships in Athletics and the O lympic record of 9.63 s set in 2012 London Olympics Games by Usain Bolt. The application of VirtualDub Programme allowed the acquisition of basic kinematical variables such as step length and step frequency parameters of 100 m sprint from video footage provided by NBC TV station, BBC TV station. This data was compared with other data available on the web and data published by the Scientific Research Project Office responsible on behalf of IAAF and the German Athletics Association (DVL). The main hypothesis was that the step length is the main factor that determines running speed in the 10 and 20 m sections of the entire 100 m distance. Bolt’s anthropometric advantage (body height, leg length and liner body) is not questionable and it is one of the factors that makes him faster than the rest of the finalists from each three competitions. Additionally, Bolt’s 20 cm longer stride shows benefit in the latter part of the race. Despite these factors, he is probably able to strike the ground more forcefully than rest of sprinters, relative to their body mass, therefore, he might maximize his time on the ground and to exert the same force over this period of time. This ability, combined with longer stride allows him to create very high running speed - over 12 m/s (12.05 -12.34 m/s) in some 10 m sections of his three 100 m performances. These assumption confirmed the application of Ballerieich's formula for speed development. In most 10 m sections of the 100 m sprint, the step length was the parameter that significantly determined the increase of maximal running speed, therefore, distinguishing Bolt from the other finalists.

7

Swimming Speed of The Breaststroke Kick

100%

Strzała M., Krężałek P., Kaca M., Głąb G., Ostrowski A., Stanula A., Tyka A.

Journal of Human Kinetics

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2012

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vol. 35

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issue 1

133-139

EN

The breaststroke kick is responsible for a considerable portion of the forward propulsion in breaststroke swimming. The aim of this study was to measure selected anthropometric variables and functional properties of a swimmer’s body: length of body parts; functional range of motion in the leg joints and anaerobic power of the lower limbs. Chosen kinematic variables useful in the evaluation of swimming performance in the breaststroke kick were evaluated. In the present research, swimming speed using breaststroke kicks depended to the largest extent on anaerobic endurance (0.46, p < 0.05 partial correlations with age control). In addition, knee external rotation and swimming technique index had an impact on swimming speed and kick length (both partial correlations with age control 0.35, p < 0.08). A kinematic analysis of the breaststroke kick hip displacement compatible with horizontal body displacement was significantly negatively correlated with foot slip in the water opposite to body displacement (partial correlations: with leg length control -0.43, p < 0.05; with shank length control -0.45, p < 0.05, respectively). Present research and measurements of selected body properties, physical endurance and kinematic movement analysis may help in making a precise determination of an athlete’s talent for breaststroke swimming.

8

Spatial kinematic analysis of double 4-link coupler used in low-floor tram powertrains

89%

Maniowski M., Czauderna T., Maniowski M., Czauderna T.

Archive of Mechanical Engineering

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2016

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vol. 63

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issue 1

9

Body Composition and Kinematic Analysis of the Grab Start in Youth Swimmers

88%

Alptekin A.

Journal of Human Kinetics

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2014

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vol. 42

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issue 1

15-26

EN

The purposes of this study were to compare the kinematic variables in youth swimmers during the grab start between sexes and to investigate the relationship between body composition and kinematic variables of the participants. Six female (Mage = 13.71 ± 0.49 yrs) and seven male (Mage = 14.00 ± 1.07 yrs) swimmers participated in this study. All participants were required to perform grab start tests in random order (three trials by each participant), while the best attempt was analyzed. Nineteen kinematic parameters consisting of block time, flight time, flight distance, total time, total distance, horizontal and vertical displacement of the center of mass (CM) at take-off, horizontal and vertical displacement of the CM at entry, height of take-off and entry, relative height of take-off, horizontal and vertical velocity of the CM at take-off, horizontal and vertical velocity of the CM at entry, angle of take-off, angle of entry and angle of knee at block were analyzed. Out of the 19 evaluated kinematic parameters, a statistical difference between the female and male group was found only in the total distance. Therefore, both female and male groups are considered as only one group and merged after analyzing the results. Statistical analysis showed positive and negative correlations between horizontal / vertical velocity of CM at take-off and several kinematic variables (e.g. angle of entry (rhorizontal = -.868, p=.000 / rvertical = .591, p=.02), total distance (rhorizontal = .594, p=.02 / rvertical = .54, p=.04), and height of take-off (rvertical = .888, p=.000), respectively). On the other hand, positive and negative correlations were found between somatotype components and several kinematic variables (e.g. horizontal displacement of CM at entry (rendomorphy = -.626, p=.013), angle of entry (rmesomorphy = -.686, p=.005 / rectomorphy = .52, p=.047), total distance (rendomorphy = -.626, p=.012), and height of take-off (rendomorphy = -.633, p=.011 / rectomorphy = .515, p=.05)). In conclusion, results show that in order to be successful at grab start performance, a swimmer should target to get higher horizontal velocity of CM at take-off and optimize the angle of take-off so this movement form supplies more total distance to the swimmer. Coaches should consider improving start performance and adding start training to regular training sessions. Moreover, youth male and female swimmers can participate together in the grab start training

10

Analysis of swimming flip turn kinematic variables of people with disabilities

51%

Nosiadek A., Gajer B.

Health Promotion & Physical Activity

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2022

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vol. 21

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issue 4

27-37

PL

Cel pracy: Celem badań była próba przeprowadzenia analizy zmiennych kinematycznych w poszczególnych fazach nawrotu parapływackiego. Materiał i metody: Zbadano 2 zawodników z niepełnosprawnością (klasy S6 i S14) w wieku 16 i 21 lat. U każdego badanego indywidualnie zarejestrowano kamerami GOPRO trzy rodzaje nawrotów koziołkowych z różnymi prędkościami dopływania do ściany. Filmy opracowano z wykorzystaniem programu Kinovea. Wyniki: Wyróżniono fazy nawrotu parapływackiego oraz przeprowadzono analizę zmiennych kinematycznych: sumaryczny czas nawrotu, prędkość dopłynięcia do ściany i prędkość odbicia, odległość od ściany, głębokość zanurzenia oraz kąt odbicia. Obliczone wartości zmiennych wykazywały indywidualne zróżnicowanie i związane były z rodzajem niepełnosprawności zawodników. Wnioski: Faza obrotu właściwego, jako najdłużej trwająca część nawrotu koziołkowego, wraz z analizą zmiennych umożliwia wprowadzenie istotnych zmian w celu skrócenia czasu nawrotu parapływackiego. Zdefiniowane zmienne oraz ich wzajemne zależności znacząco wpływają na realizację nawrotu. Kąt odbicia i prędkość odbicia zawodnika od ściany w znacznym stopniu warunkują dalszy przebieg i efektywność nawrotu. Zindywidualizowana analiza zmiennych kinematycznych pozwala na obserwację występujących przeciążeń podczas nawrotu koziołkowego, a tym samym umożliwia niezwłoczną korektę i zminimalizowanie ryzyka wystąpienia negatywnych skutków intensywnego treningu pływackiego.

EN

Objective: The aim of this study was to attempt to analyse the kinematic variables in the different phases of para-swim turnaround in swimming. Material and methods: two athletes with disabilities (classes S6 and S14) aged 16 and 21 years were studied. In each subject, three types of somersaults at different speeds to the wall were individually recorded with GOPRO cameras. The videos were processed using Kinovea software. Results: The phases of the para-swim flip turn were distinguished and the following kinematic variables were analysed: total recurrence time, wall swim speed and rebound speed, distance from the wall, immersion depth and rebound angle. The calculated values of the variables showed individual variation and were related to the type of disability of the athletes. Conclusions: The pivot phase proper, as the longest part of the para-swimming turnaround, together with the analysis of the variables, allows significant changes to be made in order to reduce the time of the para-swimming turnaround. The defined variables and their interrelationships significantly affect the execution of the turnaround. The angle of rebound and the speed of the athlete's rebound from the wall significantly determine the subsequent course and efficiency of the turnaround. The individualised analysis of the kinematic variables makes it possible to observe the overloads occurring during the para-swimming turnaround and thus enable immediate correction and minimise the risk of negative effects of intensive swimming training.

Refine search results

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

Kinematic Analysis of Canoe Stroke and its Changes During Different Types of Paddling Pace - Case Study

Analysis of Match Performance of Full-backs from Selected European Soccer Leagues

Validity of Mechanical Power Output Measurement at Bench Press Exercise

Kinematic Structure at the Early Flight Position in Ski Jumping

A Kinematics Analysis Of Three Best 100 M Performances Ever

Swimming Speed of The Breaststroke Kick

Spatial kinematic analysis of double 4-link coupler used in low-floor tram powertrains

Body Composition and Kinematic Analysis of the Grab Start in Youth Swimmers

Analysis of swimming flip turn kinematic variables of people with disabilities