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Yao Y, Niu X. Construction of a physical fitness evaluation index system and model for high-level freestyle skiing aerials athletes in China. PLoS One 2023; 18:e0295622. [PMID: 38064528 PMCID: PMC10707543 DOI: 10.1371/journal.pone.0295622] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
OBJECTIVE This study aims to enhance the competitive level of Chinese freestyle skiing aerials athletes by developing a specialized physical fitness evaluation index system and model tailored for high-level Chinese athletes. This system intends to provide theoretical references and training monitoring schemes in preparation for the 25th Milan Winter Olympics. METHODS A study was conducted on 29 high-level Chinese freestyle skiing aerials athletes. Physical fitness test indexes were selected using a literature review, expert interviews, and questionnaire surveys, and athletes were tested. Athletes were ensured to be in optimal physical condition before testing. Based on the test results, the representative indexes of the evaluation system are finally determined by combining R-type clustering analysis, multiple linear regression analysis. Determine index weights through weight questionnaires and normalization, and develop evaluation standards through methods such as percentile counting and weighted scoring. RESULTS Physical fitness evaluation system for Chinese freestyle skiing aerialists includes three aspects: evaluation index, index weight, and evaluation standard. The evaluation indexes include 3 first-level, 11 second-level, and 11 third-level indexes of body form, physiological function, and physical quality. In the evaluation weight, physical quality is ranked first, and physiological function and body form rank second and third, respectively. The evaluation standard consists of a scoring evaluation standard and a rating evaluation standard. Based on the index system, this study constructs the general and ideal physical fitness model of China's high-level freestyle aerials athletes. CONCLUSION The constructed physical fitness evaluation system effectively represents physical fitness development status of high-level freestyle skiing aerials athletes, providing a basis for creating personalized training plans. The established model serves as a reference for athletes' physical fitness development objectives.
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Affiliation(s)
- Youwei Yao
- School of Sports Training, Shenyang Sport University, Shenyang, China
| | - Xuesong Niu
- School of Social Sports, Shenyang Sport University, Shenyang, China
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Natrup J, de Lussanet MHE, Boström KJ, Wagner H. Angular velocity around the longitudinal axis in combination with head movements of springboard divers during twisted somersaults. Sports Biomech 2023; 22:282-299. [PMID: 35098878 DOI: 10.1080/14763141.2022.2032297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The ability of springboard divers to perform and control difficult elements with multiple twisted somersaults before entering the water is of great interest for coaches and researchers. In order to produce twists within somersaults, divers use both 'contact' and 'aerial' techniques. After completing body axes rotations, head movements seem to be important, as they enable visual information in the air. The current study aims at investigating angular velocities around the longitudinal axis in combination with head movements of 13 springboard divers during twisted somersaults. Divers performed forward and backward somersaults with different numbers of half twists. The results revealed maximum longitudinal axis angular velocities between 500°/s and 1300°/s. Moreover, results showed that the use of contact technique was greater in twisted somersaults with backward approaches, and thus higher angular velocities could be achieved. While finishing the twists, head movements in the opposite direction to the longitudinal axis rotation occurred, which allow divers to orient themselves. Twist speeds influenced athletes' head movements to have greater angles and greater rotational velocities. Therefore, it is concluded that fast head movements are necessary in difficult twisted dives to allow orientation in the short phase between finishing the twist and entering the water surface.
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Affiliation(s)
- Jens Natrup
- Department of Movement Science, University of Muenster, Muenster, Germany
| | - Marc H E de Lussanet
- Department of Movement Science, University of Muenster, Muenster, Germany.,Otto Creutzfeld Center, University of Muenster, Muenster, Germany
| | - Kim Joris Boström
- Department of Movement Science, University of Muenster, Muenster, Germany
| | - Heiko Wagner
- Department of Movement Science, University of Muenster, Muenster, Germany.,Otto Creutzfeld Center, University of Muenster, Muenster, Germany
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3
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Horri Z, Lenjannejadian S, Boroujeni MR, Farazin A. Kinematics of take-off phase in successful and unsuccessful performances of gymnastic somersault: an experimental study. SPORT SCIENCES FOR HEALTH 2021. [DOI: 10.1007/s11332-021-00797-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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4
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Shield S, Jericevich R, Patel A, Jusufi A. Tails, Flails, and Sails: How Appendages Improve Terrestrial Maneuverability by Improving Stability. Integr Comp Biol 2021; 61:506-520. [PMID: 34050735 PMCID: PMC8633431 DOI: 10.1093/icb/icab108] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 04/27/2021] [Accepted: 05/27/2021] [Indexed: 12/20/2022] Open
Abstract
Trade-offs in maneuverability and stability are essential in ecologically relevant situations with respect to robustness of locomotion, with multiple strategies apparent in animal model systems depending on their habitat and ecology. Free appendages such as tails and ungrounded limbs may assist in navigating this trade-off by assisting with balance, thereby increasing the acceleration that can be achieved without destabilizing the body. This comparative analysis explores the inertial mechanisms and, in some cases, fluid dynamic mechanisms by which appendages contribute to the stabilization of gait and perturbation response behaviors in a wide variety of animals. Following a broad review of examples from nature and bio-inspired robotics that illustrate the importance of appendages to the control of body orientation, two specific cases are examined through preliminary experiments: the role of arm motion in bipedal gait termination is explored using trajectory optimization, and the role of the cheetah’s tail during a deceleration maneuver is analyzed based on motion capture data. In both these examples, forward rotation of the appendage in question is found to counteract the unwanted forward pitch caused by the braking forces. It is theorized that this stabilizing action may facilitate more rapid deceleration by allowing larger or longer-acting braking forces to be applied safely.
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Affiliation(s)
- Stacey Shield
- African Robotics Unit, University of Cape Town, South Africa
| | | | - Amir Patel
- African Robotics Unit, University of Cape Town, South Africa
| | - Ardian Jusufi
- African Robotics Unit, University of Cape Town, South Africa.,Locomotion in Biorobotic and Somatic Systems, Max Planck Institute for Intelligent Systems, Heisenbergstrasse 3, 70569, Germany
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5
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Natrup J, de Lussanet MHE, Boström KJ, Lappe M, Wagner H. Gaze, head and eye movements during somersaults with full twists. Hum Mov Sci 2020; 75:102740. [PMID: 33307374 DOI: 10.1016/j.humov.2020.102740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 11/27/2020] [Accepted: 11/27/2020] [Indexed: 11/28/2022]
Abstract
Somersaults with or without twists are the most important elements in sports such as gymnastics or trampolining. Moreover, to perform elements with the highest possible difficulty gymnasts should show good form and execution during the flight phase. In order to ensure perfect body control and a safe landing, gaze behavior has been proven to be crucial for athletes to orientate in the air. As eye movement and head movement are closely coordinated, both must be examined while investigating gaze behavior. The aim of the current study is to analyze athletes' head motion and gaze behavior during somersaults with full twists. 15 skilled trampoline gymnasts performed back straight somersaults with a full twist (back full) on the trampoline. Eye movement and head movement were recorded using a portable eye-tracking device and a motion capture suit. The results indicate that gymnasts use the trampoline bed as a fixation point for orientation and control the back full, whereas the fixation onsets for athletes of a better performance class occur significantly later. A strong coordination between gymnasts' eye movement and head movement could be determined: stabilizing the gaze during the fixation period, the eyes move in combination with the head against the twisted somersault direction to counteract the whole body rotation. Although no significant differences could be found between the performance classes with regard to the maximum axial head rotations and maximum head extensions, there seems to be a trend that less skilled gymnasts need orientation as early as possible resulting in greater head rotation angles but a poorer execution.
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Affiliation(s)
- Jens Natrup
- Department of Movement Science, University of Muenster, Muenster, Germany.
| | - Marc H E de Lussanet
- Department of Movement Science, University of Muenster, Muenster, Germany; Otto Creutzfeld Center, University of Muenster, Muenster, Germany
| | - Kim Joris Boström
- Department of Movement Science, University of Muenster, Muenster, Germany
| | - Markus Lappe
- Otto Creutzfeld Center, University of Muenster, Muenster, Germany; Institute for Psychology, University of Muenster, Muenster, Germany
| | - Heiko Wagner
- Department of Movement Science, University of Muenster, Muenster, Germany; Otto Creutzfeld Center, University of Muenster, Muenster, Germany
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Marinšek M, Čuk I. EFFECTS OF DIFFERENT LEG LOADINGS AT TAKE-OFF ON LANDING CHARACTERISTICS IN TWISTING SOMERSAULTS. SCIENCE OF GYMNASTICS JOURNAL 2019. [DOI: 10.52165/sgj.11.3.289-298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The purpose of the study was to determine whether take-off asymmetry affects landing asymmetry. Eleven male gymnasts performed forward and backward somersaults with 1/2, 1/1, and 3/2 twists. The leading leg for each participant was defined according to the twisting direction. Ground reaction forces under each foot were measured with Parotec insoles. Absolute and relative measures of lateral asymmetry were used as dependent variables. Three-way ANOVA and a series of one-way ANOVAs were used to determine the main effects between take-off and landing. A series of paired t-tests with Bonferroni corrections were used to find differences between the leading and non-leading legs. Maximal ground reaction forces showed that the leading leg was set out to a higher load at take-off than the non-leading leg for twisting somersaults. There were no statistically significant differences found in the maximal ground reaction force between the legs at landings. Index of bilateral asymmetry indicated landings with negligible asymmetry. However, the maximal force differences between the legs in somersault 3/2 were higher when compared to other somersault variations. No evidence was found to affirm that the asymmetry at take-off affects asymmetry at landing in a twisting somersault. Presumably, gymnasts can take corrective measures during the aerial phase of the twisting somersault that effectively diminish the tilt of the body and enable gymnasts to prepare for the landing with small proportional asymmetry. Prudence is required as these proportions rise in the quantity of load with the height of the somersault.
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Yeadon MR, Hiley MJ. The limits of aerial and contact techniques for producing twist in reverse 1½ somersault dives. Hum Mov Sci 2019; 66:390-398. [PMID: 31170677 DOI: 10.1016/j.humov.2019.05.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 10/26/2022]
Abstract
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that can be produced in a reverse 1½ somersault dive from a three-metre springboard using various aerial and contact twisting techniques. The segmental inertia parameters of an elite springboard diver were used in the simulations and lower bounds were placed on the durations of arm and hip angle changes based on recorded performances of twisting somersaults. A limiting dive was identified as that producing the largest possible odd number of half twists. Simulations of the limiting dives were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist after a flight time of 1.5 s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that the upper limits ranged from 3½ to 5½ twists with arm abduction ranges lying between 8° and 23°. Similar results were obtained when the inertia parameters of two other springboard divers were used. It may be concluded that a reverse 1½ somersault dive using aerial asymmetrical arm and hip movements to produce 5½ twists is a realistic possibility. To accomplish this limiting dive the diver needs to be able to coordinate the timing of configurational changes with the progress of the twist with a precision of 10 ms or better.
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Affiliation(s)
- M R Yeadon
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK.
| | - M J Hiley
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
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Yeadon MR, Hiley MJ. The limits of aerial techniques for producing twist in forward 1½ somersault dives. Hum Mov Sci 2018; 58:97-107. [PMID: 29408164 DOI: 10.1016/j.humov.2018.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 01/13/2018] [Accepted: 01/14/2018] [Indexed: 11/18/2022]
Abstract
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that can be produced in a forward 1½ somersault dive from a three-metre springboard using various aerial twisting techniques. The segmental inertia parameters of an elite springboard diver were used in the simulations and lower bounds were placed on the durations of arm and hip angle changes based on recorded performances of twisting somersaults. A limiting dive was identified as that producing the largest possible whole number of twists. Simulations of the limiting dives were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist after a flight time of 1.5 s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that the upper limits ranged from two to five twists with arm abduction ranges lying between 6° and 17°. Similar results were obtained when the inertia parameters of two other springboard divers were used.
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Affiliation(s)
- M R Yeadon
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK.
| | - M J Hiley
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK
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9
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Twist limits for late twisting double somersaults on trampoline. J Biomech 2017; 58:174-178. [PMID: 28549598 DOI: 10.1016/j.jbiomech.2017.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 05/03/2017] [Accepted: 05/05/2017] [Indexed: 11/21/2022]
Abstract
An angle-driven computer simulation model of aerial movement was used to determine the maximum amount of twist that could be produced in the second somersault of a double somersault on trampoline using asymmetrical movements of the arms and hips. Lower bounds were placed on the durations of arm and hip angle changes based on performances of a world trampoline champion whose inertia parameters were used in the simulations. The limiting movements were identified as the largest possible odd number of half twists for forward somersaulting takeoffs and even number of half twists for backward takeoffs. Simulations of these two limiting movements were found using simulated annealing optimisation to produce the required amounts of somersault, tilt and twist at landing after a flight time of 2.0s. Additional optimisations were then run to seek solutions with the arms less adducted during the twisting phase. It was found that 3½ twists could be produced in the second somersault of a forward piked double somersault with arms abducted 8° from full adduction during the twisting phase and that three twists could be produced in the second somersault of a backward straight double somersault with arms fully adducted to the body. These two movements are at the limits of performance for elite trampolinists.
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10
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Barker LA, Harry JR, Dufek JS, Mercer JA. Aerial Rotation Effects on Vertical Jump Performance Among Highly Skilled Collegiate Soccer Players. J Strength Cond Res 2017; 31:932-938. [DOI: 10.1519/jsc.0000000000001557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Yeadon MR, Hiley MJ. The control of twisting somersaults. J Biomech 2014; 47:1340-7. [DOI: 10.1016/j.jbiomech.2014.02.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Revised: 01/15/2014] [Accepted: 02/06/2014] [Indexed: 11/28/2022]
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12
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The limits of aerial twisting techniques in the aerials event of freestyle skiing. J Biomech 2013; 46:1008-13. [PMID: 23235111 DOI: 10.1016/j.jbiomech.2012.11.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Revised: 11/05/2012] [Accepted: 11/10/2012] [Indexed: 11/20/2022]
Abstract
In the aerials event of freestyle skiing, athletes perform three somersaults with up to five twists. This study investigated the twisting limits of such movements using a computer simulation model of aerial movement. The abilities of various asymmetrical arm and hip techniques to produce twist during flight were investigated using 10 simulations to maximise twist and allow reorientation prior to landing. It was found that 4-6 twists could be produced during three somersaults. The main limiting factor was the increased whole body frontal moment of inertia due to the equipment which restricted the amount of tilt resulting from an asymmetrical arm movement. It was concluded that reductions in equipment mass might make such movements easier to achieve but would be unlikely to allow advances beyond the limits found.
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13
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Domire ZJ, Challis JH. An induced energy analysis to determine the mechanism for performance enhancement as a result of arm swing during jumping. Sports Biomech 2010; 9:38-46. [DOI: 10.1080/14763141003692639] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Requejo PS, McNitt-Gray JL, Flashner H. Modification of landing conditions at contact via flight. BIOLOGICAL CYBERNETICS 2004; 90:327-336. [PMID: 15221393 DOI: 10.1007/s00422-004-0473-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2003] [Accepted: 02/18/2004] [Indexed: 05/24/2023]
Abstract
Weight-bearing tasks performed by humans consist of a series of phases with multiple objectives. Analysis of the relationship between control and dynamics during successive phases of the tasks is essential for improving performance without sustaining injury. Experimental evidence regarding foot landings suggests that the distribution of momentum among segments at contact influences stability during interaction with the landing surface. In this study, we hypothesized that modification of control in one subsystem, in our case shoulder torque, during the flight phase of an aerial task would enable the performer to maintain behavior of other subsystems (e.g.lower extremity kinematics) and initiate contact with momentum conditions consistent with successful task performance. To test this hypothesis, an experimentally validated multilink dynamic model that incorporated modifications in shoulder torque was used to simulate the flight phase dynamics of overrotated landings. The simulation results indicate that modification in shoulder torque during the flight phase enables gymnasts to maintain lower extremity kinematics and initiate contact with trunk angular velocities consistent with those observed during successful landings. These results suggest that modifications in the control logic of one subsystem may be sufficient for achieving both global and local task objectives of landing.
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Affiliation(s)
- Philip S Requejo
- Biomechanics Research Laboratory, University of Southern California, Los Angeles, CA 90089-0652, USA
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15
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Abstract
The timing of actions to initiate and stop twist is critical to successful performance of the twisting and somersault rotations in 3m springboard dives. An important indicator of timing differences among subjects is the timing of hip flexion and extension. The purpose of this study was to quantify the timing and magnitude of hip flexions and extensions in the forward one and one half twisting dive with one twist. The timing and magnitude of hip flexion and extension of ten divers ranging in ability from New Zealand National to elite International standard were quantified using three-dimensional videography and analysis techniques. A Spearman (rho) correlation with p<.05 required for significance was conducted to determine the relationship between each of the variables and ability. The results indicated that skilled divers had more flight time than less skilled divers (rho=-.79), less hip flexion at takeoff (rho=.66), less pre-twist flexion (rho=.86), greater post-twist hip flexion, and had more time from the time of maximum post-twist flexion to entry than less skilled divers (rho=-.81). It was concluded that divers who currently initiate twist from a 'kick out' should learn to initiate twist without a 'kick out' and reduce hip flexion at takeoff to increase height and flight time.
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Affiliation(s)
- R H Sanders
- School of Biomedical and Sport Science, Edith Cowan University, Perth, Western Australia
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16
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Abstract
I used a computer simulation model of aerial movement to investigate the techniques for producing and controlling rotations of the human body during free flight. I found that the rotational motion can change from a twisting somersault to a nontwisting somersault by flexing at the hips at a suitable time. Twist may be produced in the aerial phase by means of asymmetrical movements of arms or hips, which result in a tilting of the longitudinal axis away from the plane perpendicular to the angular momentum vector. Asymmetrical movements may also remove the tilt and stop the twist. Elite performances of twisting somersaults are characterized by a large contribution from aerial twisting techniques. A progression of movements is presented for learning a double somersault with one and a half twists in the second somersault.
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Affiliation(s)
- M R Yeadon
- Department of Sports Science, Loughborough University, United Kingdom
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Abstract
This project sought to break down high jump twist rotation into portions contributed by angular momentum and those contributed by rotational action and reaction ("catting"). Five male and 5 female high jumpers were studied with three-dimensional film/video analysis procedures. The hip twist angle at the peak was broken down into an initial twist angle at takeoff and the subsequent twist rotation accumulated between takeoff and the peak. The latter was in turn broken down into rotations contributed by the twisting component of angular momentum and rotations contributed by catting. It was found that the contribution of catting to the twist rotation was at least as large as that of the angular momentum. The important contribution of catting to the twist rotation introduces the possibility that defects in its execution might play a role in the problems that some high jumpers have with twist rotation.
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Abstract
At the 1988 Seoul Olympic Games, four double somersault dismounts with one twist and four double somersault dismounts with two twists were filmed using two 16 mm cameras during the men's horizontal bar competitions. Contributions to tilt angle reached at the midtwist position, determined using computer simulations based on modifications of the data obtained from film, were used as measures of the twisting potential of various techniques. The amount of tilt produced was greater when total twist was greater and when the body was tucked rather than straight. The twisting techniques used varied with the timing of the twist within the two somersaults. Contact contributions were larger when there was more twist in the first somersault. When there was little or no twist in the first somersault, the major contribution came from aerial techniques that comprised mainly arm movements and asymmetrical hip movements in the flight phase.
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Abstract
Theoretical analyses have shown that rotations of a rigid body about the principal axis corresponding to the intermediate principal moment of inertia are unstable. This poses a potential problem for gymnasts who perform double somersaults without twist in a layout configuration. A computer simulation model is used to investigate configurational strategies for controlling such movements. It is shown that the build up of twist is not reduced by abduction of the arms but can be controlled by adopting a configuration with sufficient body flexion. For somersaults with a straight body, control in the form of asymmetrical arm abduction accelerations, based upon twist angular velocity and angular acceleration, is capable of preventing a build up of twist providing that the feedback time delay is less than a quarter somersault.
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Affiliation(s)
- M R Yeadon
- Department of Sports Science, Loughborough University, U.K
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20
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Abstract
This study was designed to investigate the effect of ability on technique in the forward somersault with half twist (Barani) and the forward somersault with one and one half twists (Rudi) on the trampoline. Eleven trampolinists ranging in ability from elite (national representative) to early intermediate (regional representative) were analyzed using three-dimensional analysis techniques. Cumulative twist angle, rate of twist, angle of tilt of the twist axis, chest rotation, hip angle, and hip lateral flexion angle were measured. Characteristics of the arm actions were also assessed using an internal frame of reference. To generate twist in the Baranis, trampolinists tilted the axis between 5° and 14°; the amount of tilt was inversely related to ability (p < .05). In the Rudis, subjects tilted the axis between 15° and 23° using more asymmetrical arm actions and larger and more rapid hip extensions, hip lateral flexions, and chest rotations than in the Baranis. The timing and magnitude of the actions differed among the subjects and were related to ability.
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Abstract
At the 1992 Olympic Games six full twisting double somersault dismounts were recorded with two video cameras during the rings individual apparatus finals in the men's Artistic Gymnastics competition. Angles describing body configuration were determined from video data and were input, together with initial orientation angle values and angular momentum components, into a computer simulation model of aerial movement. Mean absolute deviations between simulation and video after the completion of one half twist were 0.01 rev for somersault, 2.8° for tilt, and 0.08 rev for twist. When the estimate of the initial tilt angle was adjusted by up to 1° these deviations fell to 1.6° for tilt and 0.02 rev for twist. All 6 competitors produced the majority of the tilt using aerial techniques that were predominantly asymmetrical movements of the arms. Contributions to the subsequent removal of tilt were determined using reverse simulations, and again arm movements were the main contributors.
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Abstract
An overview of performance-related research in sports biomechanics is presented describing the relevant techniques of data analysis and data processing together with the methods used in experimental and theoretical studies. Advances in data collection and processing techniques which are necessary for the future development of sports biomechanics research are identified. The difficulties associated with experimental studies in sports biomechanics are described with examples of the different approaches that have been used. The strengths and weaknesses of theoretical studies are discussed with examples drawn from a number of sports. It is concluded that progress in performance-related research will result from the application of a suitable combination of theoretical and experimental approaches to those sports in which technique is the primary requirement for success.
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Affiliation(s)
- M R Yeadon
- Department of Sports Science, Loughborough University, UK
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23
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Abstract
At the 1991 World Student Games, eight reverse 1 1/2 somersault dives with 2 1/2 twists were recorded during the men's finals in the 1 m and 3 m springboard diving competitions using two video cameras. Angles describing body configuration were determined from video data and were input, together with initial orientation angle values and angular momentum components, into a computer simulation model of aerial movement in order to predict body orientation in space. Mean absolute deviations between simulation and video after the completion of one twist were 0.02 rev for somersault, 2.3 degrees for tilt and 0.04 rev for twist. Contributions to the tilt angle after one twist were used as measures of the twisting potential of various techniques and were determined using simulations based on modifications of the video data. Seven of the eight competitors produced the majority of the tilt using aerial techniques which were predominantly asymmetrical movements of the arms and hips, although the mean contribution from contact techniques amounted to one-third of the total tilt.
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Affiliation(s)
- M R Yeadon
- Department of Physical Education, Sports Science and Recreation Management, Loughborough University of Technology, UK
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