Giant Swing Research Articles

Technical elements on the rings in men's artistic gymnastics—a systematic review

Although rings can move freely in all possible directions, by which they differ from all other apparatuses, physical performance at highest level is essetial in men’s artistic gymnastics to fulfill the exercise’s technical requirements in the interest of effective and accurate performance. We have aimed to compile the scientific evidence regarding exercises on the rings in men’s artistic gymnastics and, based on it, to investigate the necessary requirements for their successful realization. In regard to Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines, the database search (Google Scholar, PubMed, Web of Science and Research Gate) has identified 5759 potential studies. Original cross-sectional studies published between 2000 and 2022 written in English, active male gymnasts who do not suffer from injury as a sample of participants, and studies that have evaluated different types of elements on the rings were reconsidered. Lastly, 15 full-text studies were identified. A total of seven elements were evaluated, four strength elements (swallow, Azarian, iron cross and support scale), two dismounts (double backflip straight and double backflip straight with a 360◦ turn), and one swing element (backward giant swing). Two studies have conducted a dismount kinematic analysis, another four strength elements electromyography, while two studies have used force plates to evaluate the required specific strength for their successful performance. Hence, handgrip strength, pectoralis muscles, teres major, deltoids and serratus anterior are crucial. In addition, handgrip strength, proper swing movement, lateral arm movement during the descending phase, and hip flexor/extensor muscle activity are also essential for both giant swings and dismounts. Progressive strength upgrade of key movements in younger gymnasts is necessary to make successful generations on the rings. Therefore, in order to upgrade the above, researchers and scientists should discover a method for providing more relevant and updated information for practitioners, i.e., coaches and gymnasts.

채점규칙 변경에 따른 기계체조 세계선수권대회 링 연기구성의 변화

The purpose of this study was to analyze participants 32 players from 8 team Final, 4 Korean players ranked 9th, and a total of 36 players to the revised scoring rules. First, in Group I, C-difficulty swing fwd. with straight arms. to hdst.(2s) and Uprise bwd. or giant swing with straight arms.(2s) suitable for the requirements, and D-difficulty Jonason and C-difficulty Yamawaki should be performed. Second, Group II thought that either D-difficulty nakayama or Azarian, which can be usefully postponed even in the 2022 rules, should be performed. As the swallow form of roll bwd. swallow with str. arm and body to slow(2s) is lowered to E-difficulty and determined to have the same difficulty as From cross. press to swallow(2s), the selection of D-difficulty Hirondelle and technology is important. Third, Group III It is believed that players and coch will have to decide what skills to perform. but Players are thought to need to acquire technologies such as Uprise bwd. to inverted cross (2s), where technologies in the form of inverted cross have been determined to be upgraded from D to E difficulty. Fourth, Group IV it is double salto bwd. t. with 2/1t. thought that performing a perfect landing rather than a performance may produce better results. Fifth, Team Score can be said to be essential for even difficulty and stable performance of players participating in the game, and it is believed that not only high-level skills but also skills should be improved.

Pathology and surgical outcomes of anterior traumatic shoulder instability in gymnasts (235)

Objectives:For shoulders of artistic gymnasts, stability against various forces such as weight bearing, torsion, and traction is required as well as wide range of motion. The prevalence of shoulder instability in gymnasts has been reported to be high, particularly in female gymnasts; however, there has been no report on its pathology and the surgical outcomes. The purpose of this study was to retrospectively investigate the pathology and surgical outcomes of anterior traumatic shoulder instability in gymnasts.Methods:The subjects of this study were 18 shoulders of 16 gymnasts that underwent arthroscopic surgery for anterior traumatic shoulder instability. They consisted of 4 male and 14 female shoulders with a mean age of 18 years (range, 16-20). The mean follow-up was 30 months (range, 10-66 months). All surgeries were performed arthroscopically, and procedures were determined according to the intraoperative findings. Patients were immobilized with a brace for 3 weeks and started range of motion exercise after the immobilization period. Hand-stand or hanging were normally allowed at 3 month after surgery according to patients’ functional recovery. We investigated injury mechanism, intraoperative findings, surgical procedures, times to start hand-stand or hanging and to start giant swing, time to complete return to gymnastics, and recurrence of instability.Results:Three shoulders experienced dislocations that self-reduction was impossible. The remaining 15 shoulders had self-reducible dislocations or subluxations, and 10 of 15 shoulders were injured with the shoulder hyper-flexed: e.g., pulling up hands during somersaults; pushing off the vault (Figure). Bankart lesion was identified during surgery in 14 shoulders including one bony Bankart lesion. Capsular tear was found in 5 shoulders, and only one lesion was concomitant with Bankart lesion. All lesions were arthroscopically repaired. We additionally performed rotator interval closure in 10 shoulders, superior labrum repair in 13, and rotator cuff repair in 2. One patient retired from gymnastics immediately after surgery, and 2 patients were lost to follow-up. The remaining 13 patients returned to gymnastics. The mean time to start hand-stand or hanging was 4 months (range, 3-10 months), and that to start giant swing was 6 months (range, 3-15 months). The mean time to complete return was 9 months (range, 5-17 months). Two shoulders experienced recurrence (1 dislocation and 1 subluxation) after return to gymnastics. Both shoulders underwent revision surgery and returned to gymnastics.Conclusions:Capsular tear without Bankart lesion was more common (4 shoulder, 22%) in gymnasts than general population. The sport-related characteristics might be associated with the high incidence of capsular tear. The outcomes of arthroscopic stabilization for gymnasts was good with the high complete return rate.

2019 아시아선수권대회 링 결승경기의 연기내용 분석과 플랜치와 스왈로의 중요성

The purpose of this study was to examine the trend of exercise content and importance of the “Planche and Swallow” on the rings final in the 2019 Asian Championship. Video recordings of rings performance were collected from rings final. We found that: All gymnasts performed “Uprise backward giant swing to handstand(C value) and ”Jonsson(D value)“ in CⅠ. Five gymnasts performed Nakayama(D value) and Roll backward to swallow(F value) in CⅡ. All gymnasts performed “Uprise backward to swallow(E value)” in CⅢ. Three gymnasts performed “Double salto backward stretched with 1/1 turn(D value) and ”Double salto backward turn with 2/1 turn(E value) in CⅣ. The Planche and Swallow elements were in majority performed(32.4%) in their routines. The Planche and Swallow are very important for the value and structuring of Rings exercise.

Motion control of underactuated linkage robot based on gymnastic skill

AbstractIn this paper, a reproduction of a swing‐up and a giant swing motion of underactuated robots based on technique of the horizontal bar gymnast is discussed with focusing on an equivalent center of mass (ECM) of underactuated robots and the gymnast. At first, the behaviors of the ECM of the gymnast (ECMG) are analyzed by using a motion capturing technique and an efficient motion of the ECMG for the swing‐up and for the giant swing motion are identified from analysis results, respectively. Next, a partial linearization method, which can realize that the ECM of the Acrobot (ECMA) replicates this efficient motion, is designed and reproduces the underactuated robots the swing‐up and giant swing motion like the gymnast. Finally, an effectiveness of the proposed controller is shown by numerical simulations.

The Influence of Body Position on the Straddled Tkatchev’s Flight Phase in Men’s Horizontal Bar

To examine the effect of level of expertise on the flight phase of the straddled Tkatchev we analysed six male gymnasts (mass = 64.0 +/- 3.0kg, height = 1.67 +/- 0.06m) split into three proficiency levels Elite, Intermediate and Beginners. The preparation phase, flight phase and re-grip phase were sub-divided into ten steps that focussed on three different angularities (bar, shoulder and torso). Angular dimensions between the shoulder and torso and leg were measured using digitised points at the shoulder, trochanter major and lateral malleolus using Sportscode Elite (V10, Sportstec, Australia). A one-way ANOVA was conducted to determine differences between the groups. The results found different angles and body positions influence the flight phase of the Tkatchev. A late flexion in the downward phase with a straight position at the vertical line below the high bar influences the following movement of the Tkatchev positively. An early-piked position with a late straight/hyperextension upward phase increases the energy of the gymnast to reach a greater height above the bar. Both come with a shorten time of preparing and increased time during flight phase. By staring the preparing phase of Tkatchev before reaching the handstand position the gymnast also shorten the time of the giant swing. But then the athlete has to be faster in each execution for each segment, especially in hip flexion during the countermovement. The best time of re-grasping the bar is with a bonded body position and at an angle degree of 412°

Nonlinear control for rotational movement of cart-pendulum system using homoclinic orbit

In this paper, we deal with the control method for rotational movements of a pendulum using a separatrix. We design a controller that attains a homoclinic motion or a heteroclinic motion of the pendulum and the asymptotic stability of the cart by using a kind of forwarding control design. First, we derive a controller that converges to a homoclinic orbit via a Lyapunov function of the pendulum subsystem. Next, we give a nonlinear stabilizing controller via another Lyapunov function of the cart subsystem. Moreover, using the third Lyapunov function and adding a complementary control input, we guarantee that the pendulum converges to the homoclinic orbit and the cart is stabilized. Finally, the simulation and the experiment using the rapid controller prototyping system based on MATLAB/Simulink are performed to demonstrate the forward upward circling and the giant swing of the pendulum.

Functional phases and angular momentum characteristics of Tkatchev and Kovacs

ABSTRACTUnderstanding the technical requirements and underlying biomechanics of complex release and re-grasp skills on high bar allows coaches and scientists to develop safe and effective training programmes. The aim of this study was to examine the differences in the functional phases between the Tkatchev and Kovacs skills and to explain how the angular momentum demands are addressed. Images of 18 gymnasts performing 10 Tkatchevs and 8 Kovacs at the Olympic Games were recorded (50 Hz), digitised and reconstructed (3D Direct Linear Transformation). Orientation of the functional phase action, defined by the rapid flexion to extension of the shoulders and extension to flexion of the hips as the performer passed through the lower vertical, along with shoulder and hip angular kinematics, angular momentum and key release parameters (body angle, mass centre velocity and angular momentum about the mass centre and bar) were compared between skills. Expected differences in the release parameters of angle, angular momentum and velocity were observed and the specific mechanical requirement of each skill were highlighted. Whilst there were no differences in joint kinematics, hip and shoulder functional phase were significantly earlier in the circle for the Tkatchev. These findings highlight the importance of the orientation of the functional phase in the preceding giant swing and provide coaches with further understanding of the critical timing in this key phase.

Motor imagery beyond the motor repertoire: Activity in the primary visual cortex during kinesthetic motor imagery of difficult whole body movements

To elucidate the neural substrate associated with capabilities for kinesthetic motor imagery of difficult whole-body movements, we measured brain activity during a trial involving both kinesthetic motor imagery and action observation as well as during a trial with action observation alone. Brain activity was assessed with functional magnetic resonance imaging (fMRI). Nineteen participants imagined three types of whole-body movements with the horizontal bar: the giant swing, kip, and chin-up during action observation. No participant had previously tried to perform the giant swing. The vividness of kinesthetic motor imagery as assessed by questionnaire was highest for the chin-up, less for the kip and lowest for the giant swing. Activity in the primary visual cortex (V1) during kinesthetic motor imagery with action observation minus that during action observation alone was significantly greater in the giant swing condition than in the chin-up condition within participants. Across participants, V1 activity of kinesthetic motor imagery of the kip during action observation minus that during action observation alone was negatively correlated with vividness of the kip imagery. These results suggest that activity in V1 is dependent upon the capability of kinesthetic motor imagery for difficult whole-body movements. Since V1 activity is likely related to the creation of a visual image, we speculate that visual motor imagery is recruited unintentionally for the less vivid kinesthetic motor imagery of difficult whole-body movements.

Dynamic delayed feedback control for stabilizing the giant swing motions of an underactuated three-link gymnastic robot

This paper investigates the dynamics of the giant swing motions of an underactuated three-link gymnastic robot moving in a vertical plane by means of dynamic delayed feedback control (DDFC). DDFC, being one of useful methods to overcome the so-called odd number limitation in controlling a chaotic discrete-time system, is extended to control a continuous-time system such as a 3-link gymnastic robot with passive joint. Meanwhile, a way to calculate the error transfer matrix and the input matrix which are necessary for discretization is proposed, based on a Poincare section which is defined to regard the target system as a discrete-time system. Moreover, the stability of the closed-loop system by the proposed control strategy is discussed. Furthermore, some numerical simulations are presented to show the effectiveness in controlling a chaotic motion of the 3-link gymnastic robot to a periodic giant swing motion.

1A1-J04 強化学習を用いた大車輪ロボットの行動獲得と学習プロセスについて(進化・学習とロボティクス)

In our laboratory, we have succeeded in acquiring forward actions to various robot systems using Reinforcement Learning. We have also succeeded in acquiring a giant swing motion as dynamic task by devising its rewards. Then, the purpose of this study is to investigate the effect of probabilistic behavior which gives to the giant swing motion acquisition. Although the giant swing robot has a continuous dynamic motion such as its angle and angler velocity, its state of the motion must be divided into 216 states in order to apply the reinforcement learning. For this reason, this robot shows probabilistic behaviors. This study investigated the relationship between the performance of learning knowledge and rotation count of the learning process. Consequently, it became clear that the performance of the knowledge is deteriorated when the ratio of knowledge use of the learning process is large.

Neuromuscular onset succession of high level gymnasts during dynamic leg acceleration phases on high bar

In several athletic disciplines there is evidence that for generating the most effective acceleration of a specific body part the transfer of momentum should run in a “whip-like” consecutive succession of body parts towards the segment which shall be accelerated most effectively (e.g. the arm in throwing disciplines). This study investigated the question how this relates to the succession of neuromuscular activation to induce such “whip like” leg acceleration in sports like gymnastics with changed conditions concerning the body position and momentary rotational axis of movements (e.g. performing giant swings on high bar). The study demonstrates that during different long hang elements, performed by 12 high level gymnasts, the succession of the neuromuscular activation runs primarily from the bar (punctum fixum) towards the legs (punctum mobile). This demonstrates that the frequently used teaching instruction, first to accelerate the legs for a successful realization of such movements, according to a high level kinematic output, is contradictory to the neuromuscular input patterns, being used in high level athletes, realizing these skills with high efficiency.Based on these findings new approaches could be developed for more direct and more adequate teaching methods regarding to an earlier optimization and facilitation of fundamental movement requirements.

1A2-M03 強化学習を用いた大車輪ロボットの確率的なゆらぎの考察(進化・学習とロボティクス(1))

1A2-M03 強化学習を用いた大車輪ロボットの確率的なゆらぎの考察(進化・学習とロボティクス(1))

Relation between Probabilistic Giant Swing Behavior of a Robot and Its Reward Using Reinforcement Learning

Relation between Probabilistic Giant Swing Behavior of a Robot and Its Reward Using Reinforcement Learning

Shoulder muscles recruitment during a power backward giant swing on high bar: A wavelet-EMG-analysis

This study aimed at determining the upper limb muscles coordination during a power backward giant swing (PBGS) and the recruitment pattern of motor units (MU) of co-activated muscles. The wavelet transformation (WT) was applied to the surface electromyographic (EMG) signal of eight shoulder muscles. Total gymnast’s body energy and wavelet synergies extracted from the WT-EMG by using a non-negative matrix factorization were analyzed as a function of the body position angle of the gymnast. A cross-correlation analysis of the EMG patterns allowed determining two main groups of co-activated muscles. Two wavelet synergies representing the main spectral features (82% of the variance accounted for) discriminated the recruitment of MU. Although no task-group of MU was found among the muscles, it appeared that a higher proportion of fast MU was recruited within the muscles of the first group during the upper part of the PBGS. The last increase of total body energy before bar release was induced by the recruitment of the muscles of the second group but did not necessitate the recruitment of a higher proportion of fast MU. Such muscle coordination agreed with previous simulations of elements on high bar as well as the findings related to the recruitment of MU.

Between-subject variability of muscle synergies during a complex motor skill

The purpose of the present study was to determine whether subjects who have learned a complex motor skill exhibit similar neuromuscular control strategies. We studied a population of experienced gymnasts during backward giant swings on the high bar. This cyclic movement is interesting because it requires learning, as untrained subjects are unable to perform this task. Nine gymnasts were tested. Both kinematics and electromyographic (EMG) patterns of 12 upper-limb and trunk muscles were recorded. Muscle synergies were extracted by non-negative matrix factorization (NMF), providing two components: muscle synergy vectors and synergy activation coefficients. First, the coefficient of correlation (r) and circular cross-correlation (rmax) were calculated to assess similarities in the mechanical patterns, EMG patterns, and muscle synergies between gymnasts. We performed a further analysis to verify that the muscle synergies (in terms of muscle synergy vectors or synergy activation coefficients) extracted for one gymnast accounted for the EMG patterns of the other gymnasts. Three muscle synergies explained 89.9 ± 2.0% of the variance accounted for (VAF). The coefficients of correlation of the muscle synergy vectors among the participants were 0.83 ± 0.08, 0.86 ± 0.09, and 0.66 ± 0.28 for synergy #1, #2, and #3, respectively. By keeping the muscle synergy vectors constant, we obtained an averaged VAF across all pairwise comparisons of 79 ± 4%. For the synergy activation coefficients, rmax-values were 0.96 ± 0.03, 0.92 ± 0.03, and 0.95 ± 0.03, for synergy #1, #2, and #3, respectively. By keeping the synergy activation coefficients constant, we obtained an averaged VAF across all pairwise comparisons of 72 ± 5%. Although variability was found (especially for synergy #3), the gymnasts exhibited gross similar neuromuscular strategies when performing backward giant swings. This confirms that the muscle synergies are consistent across participants, even during a skilled motor task that requires learning.

Functional relationships between gaze behavior and movement kinematics when performing high bar dismounts – an exploratory study

PurposeThe aims of this study were, first, to investigate visual spotting and, second, to explore the functional relationships between movement structure and gaze behavior in gymnasts as they perform preparatory giant swings (traditional and scooped technique) and dismounts (single straight and double tucked salto) with increasing difficulty on the high bar. It was predicted that visual spotting would occur in all experimental tasks.MethodsRelationships between gaze behavior and movement kinematics were explored to provide a clearer picture of how gaze is interconnected with the kinematics of dismounts on the high bar. For this purpose, kinematic parameters were measured with an optical movement-analysis system while gaze behavior was measured by using a portable and wireless eye-tracking system.ResultsThe measurement of gaze behavior revealed that gymnasts use visual spotting in all three tasks showing fixations throughout the whole movement. Each task was furthermore characterized by a sequence of visual fixations that was thought to serve specific movement goals. In particular, fixations during the downswing phase of the preparatory giant swings were significantly correlated with the movement phases when beginning the hip extension and flexion in the “kick through” as well as with the athlete’s distance of flight during the dismounts.ConclusionsThe findings suggest that gymnasts can use visual spotting during preparatory giant swings and dismounts on the high bar and that there are functional relationships between different fixations and specific movement goals.

Possibility on Selection of Learning Knowledge for Motion of Giant Swing Robot by Using Reinforcement Learning

Possibility on Selection of Learning Knowledge for Motion of Giant Swing Robot by Using Reinforcement Learning

Men’s Artistic Gymnastics: a new high bar-gymnast model with sensitivity analysis

The purpose of this work was to develop a new 2D gymnast-high bar model with horizontal bar endpoint dynamics included. To this end, a three-spring high bar model was extended with a five segment gymnast model followed by evaluation and sensitivity analysis. Evaluation over more than a complete giant swing (420°) was favourable (bar position rms errors <0.017 m, center of mass angular position rms error <11°). Single parameter perturbations (10%) caused little deterioration in model performance (lower 180°of the giant swing-bar position rms errors <0.006 m, arms’ angle rms error <0.9°). Combinations of parameter perturbations gave bar position rms errors <0.008 m and arms’ angle rms error <1.8°. Model performance was most sensitive to errors in high bar stiffness values.

1A1-M06 強化学習を用いた大車輪ロボットの学習の汎化性に関する考察(進化・学習とロボティクス)

We have studied a giant swing robot whose giant swing motion can be obtained simply by applying Q learning method as one of reinforcement learning methods. In this study, we focused on learning generalization that is a problem whether a robot can choose one rotational direction. In our previous studies, it was successful that the real robot can't acquire backward rotation but forward rotation. This paper clarifies whether learning generalization can apply both forward and backward rotation on the simulation base. Learning simulation experiments take place in the various conditions like rewards, actions after rotations and learning system. As a results, it becomes obvious that trend of rotational direction can be controlled to some extent.