The Relationship Between the Perceived Movement Quality and the Kinematic Pattern of Complex Skills in Gymnastics.

The study aimed to investigate the relationship between the perceived movement quality of a gymnastics skill and its kinematic pattern, as well as the influence of expertise. Thirty participants with different levels of gymnastics expertise (n = 10 visual experts, n = 10 motor experts and n = 10 novices) were recruited for the study. They were instructed to compare the movement quality of eleven video sequences, showing different handstand - back handspring performances. To extract the kinematics, the performances were digitized. By means of an ongoing cluster analysis, the kinematic pattern as well as the pattern of the perceived movement quality of the skills were determined for each experimental group. The results of the cluster analysis of the different experimental groups were analyzed and compared. Expertise differences were found regarding the pattern of the perceived movement quality. There was a significant correlation between the dendrograms of the visual experts and the motor experts (p = .021), as well as between the dendrograms of the visual experts and the novices (p = .011). There was no significant correlation between the dendrograms of the motor experts and the novices (p = .173). The pattern of the perceived movement quality was not correlated with the holistic kinematic pattern of judged skills (p > .143). These results suggest perceptual and cognitive differences of the participants due to their different previous visual and motor experience.

Team Action Imagery and Team Cognition: Imagery of Game Situations and Required Team Actions Promotes a Functional Structure in Players' Representations of Team-Level Tactics.

A team's cognitions of interpersonally coordinated actions are a crucial component for successful team performance. Here, we present an approach to practice team action by way of imagery and examine its impact on team cognitions in long-term memory. We investigated the impact of a 4-week team action imagery intervention on futsal players' mental representations of team-level tactics. Skilled futsal players were assigned to either an imagery training group or a no imagery training control group. Participants in the imagery training group practiced four team-level tactics by imagining team actions in specific game situations for three times a week. Results revealed that the imagery training group's representations were more similar to that of an expert representation after the intervention compared with the control group. This study indicates that team action imagery training can have a significant impact on players' tactical skill representations and thus order formation in long-term memory.

Does combined strength training and local vibration improve isometric maximum force? A pilot study.

BACKGROUND: The aim of the study was to determine whether a combination of strength training (ST) and local vibration (LV) improved the isometric maximum force of arm flexor muscles. ST was applied to the left arm of the subjects; LV was applied to the right arm of the same subjects. The main aim was to examine the effect of LV during a dumbbell biceps curl (Scott Curl) on isometric maximum force of the opposite muscle among the same subjects. It is hypothesized, that the intervention with LV produces a greater gain in isometric force of the arm flexors than ST. METHODS: Twenty-seven collegiate students participated in the study. The training load was 70% of the individual 1 RM. Four sets with 12 repetitions were performed three times per week during four weeks. The right arm of all subjects represented the vibration trained body side (VS) and the left arm served as the traditional trained body side (TTS). RESULTS: A significant increase of isometric maximum force in both body sides (Arms) occurred. VS, however, significantly increased isometric maximum force about 43% in contrast to 22% of the TTS. CONCLUSION: The combined intervention of ST and LC improves isometric maximum force of arm flexor muscles. LEVEL OF EVIDENCE: III.

Gaze-Shift Patterns during a Jump with Full Turn in Male Gymnasts.

When airborne, gymnasts skillfully control their movements to achieve a successful landing. Utilizing visual information from task-specific eye-body coordination patterns (i.e., visual spotting) is thought to be important for gymnasts in the performance of aerial skills. The purpose of this study was to assess the interplay of eye movements and body movements in an aerial skill with a rotation about the longitudinal axis, namely a straight jump with full turn. Participants were 10 skilled male gymnasts (age [ M ± SD], 23.90 ± 3.28 years) and 14 male nongymnasts (20.57 ± 2.90 years). Gaze behavior during each jump was determined by measuring and integrating eye and head movement data. Results revealed two distinct gaze-shift patterns: a single-step gaze-shift pattern and a multistep gaze-shift pattern. In both patterns, skilled gymnasts stabilized their gaze prior to takeoff and again prior to landing. Whichever pattern was used, gymnasts started to stabilize their gaze on average about 110 milliseconds before landing, which was earlier than nongymnasts. The results suggest that gymnasts use visual information obtained by a particular gaze behavior to generate the necessary amount of rotation and to perform a precise landing in aerial skills involving whole-body rotations.

Option selection in whole-body rotation movements in gymnastics / Opções de movimentos na rotação da ginástica

Abstract When a gymnast performs a somersault, the linear and angular momentum along with a particular control of inertia during the flight phase constrain the possibilities for action. Given the complexity and dynamic nature of the human moving system, one could argue that there exist a particular amount of stable coordination states when performing somersaults. The goal of this study was to explore the manifold of movement options and coordination states along with their differentiating parameters for a single somersault in gymnastics based on a simple mathematical model reflecting gymnast’s rotation behavior during the flight phase. Biomechanical parameters determining rotation behavior during a somersault were systematically varied with regard to a particular set of biomechanical constraints defining a successful somersault performance. Batch simulations revealed that from 10229760 simulation cycles only 655346 (approximately 6.41%) led to successful somersault performance. A subsequent analysis of the movement option landscape for the optimum angular momentum revealed ten coordination states for a single somersault that could be clearly distinguished based on the simulation parameters. Taken the results together, it becomes apparent that it may be most advisable to perform a single somersault with a larger moment of inertia when achieving the tucked position, a longer duration to achieve the tucked position, a longer duration of staying tucked, and an intermediate moment of inertia during landing. This strategy comprises the largest amount of movement options associated with an upright landing and thus the highest probability of success when performing a single somersault.

Resumo Quando um ginasta executa um mortal, o momento linear e angular, juntamente com determinado controle de inércia durante a fase de voo, restringem as possibilidades de ação. Devido à complexidade e à natureza dinâmica do sistema do movimento humano, pode-se argumentar que existe determinada quantidade de estados coordenativos estáveis quando se executa mortais. O objetivo deste estudo foi explorar a multiplicidade de opções de movimento e estados coordenativos, juntamente com os seus parâmetros de diferenciação para um único mortal na ginástica, com base em um modelo matemático simples que reflita o comportamento da rotação do ginasta durante a fase de voo. Os parâmetros biomecânicos que determinam o comportamento da rotação durante um mortal variam sistematicamente em relação a determinado conjunto de restrições biomecânicas que definem a execução bem sucedida do mortal. Simulações em série revelaram que, a partir de 10229760 ciclos de simulação, somente 655346 (aproximadamente 6,41%) levaram ao desempenho bem sucedido do mortal. Uma análise subsequente da perspectiva de movimento para o momento angular ótimo revelou 10 estados de coordenação para um único mortal que poderiam ser claramente distinguidos com base nos parâmetros de simulação. Considerados os resultados em conjunto, torna-se evidente que seria mais aconselhável realizar um único mortal com momento de inércia maior quando se atinge a posição grupada, duração mais longa para atingir a posição grupada, duração mais longa da posição grupada, e um momento de inércia intermediário durante a aterrissagem. Essa estratégia compreende a maior quantidade de opções de movimento associados a uma aterrissagem na posição ereta e, assim, a maior probabilidade de sucesso quando se realiza um único mortal.

Does the athletes' body shape the athletes' mind? A few ideas on athletes' mental rotation performance. Commentary on Jansen and Lehmann.

Athletes exhibit differences in perceptual-cognitive abilities when compared to non-athletes. Recent theoretical developments focus on the role of the athletes' body in perceptual-cognitive tasks such as mental rotation tasks. It is assumed that the degree to which stimuli in mental rotation tasks can be embodied facilitates the mental rotation process. The implications of this assumption are discussed and ideas for future research are presented.

Movement regulation of handsprings on vault.

PURPOSE: Visual information is utilized in gymnastics vaulting. The question remains as to which informational sources are used to regulate handspring performance. The purpose of this study was to examine springboard and vaulting table position as informational sources in gymnastics vaulting. The hypothesis tested was that the approach-run and handspring kinematics change as a function of the position of the springboard and the position of the vaulting table. METHOD: Kinematic parameters of 14 female expert gymnasts' approach runs and handsprings on vault were examined, while manipulating the position of the springboard, the position of the vaulting table, or both. RESULTS: The results revealed that feet positioning during the approach run and takeoff varied predominantly as a function of the position of the springboard. The positioning of the hands on the vaulting table varied as a function of the position of the vaulting table. Furthermore, a combined manipulation of both the position of the springboard and the position of the vaulting table led to differences in feet positioning during the approach run and during takeoff, as well as to differences in hand positioning during the repulsion phase and differences in the duration of the second flight phase. CONCLUSIONS: Findings suggest that the positions of the springboard and the vaulting table are relevant informational sources in gymnastics vaulting, whereas the effect of both informational sources unfolds on different kinematic parameters. Training programs aiming to enhance gymnasts' ability to use visual information during vaulting may be fruitful in motor skill acquisition in gymnastics.

Rotational preference in gymnastics.

In gymnastics, most skills incorporate rotations about one or more body axes. At present, the question remains open if factors such as lateral preference and/or vestibulo-spinal asymmetry are related to gymnast's rotational preference. Therefore, we sought to explore relationships in gymnast's rotation direction between different gymnastic skills. Furthermore, we sought to explore relationships between rotational preference, lateral preference, and vestibulo-spinal asymmetry. In the experiment n = 30 non-experts, n = 30 near-experts and n = 30 experts completed a rotational preference questionnaire, a lateral preference inventory, and the Unterberger-Fukuda Stepping Test. The results revealed, that near-experts and experts more often rotate rightward in the straight jump with a full turn when rotating leftward in the round-off and vice versa. The same relationship was found for experts when relating the rotation preference in the handstand with a full turn to the rotation preference in the straight jump with a full turn. Lateral preference was positively related to rotational preference in non-expert gymnasts, and vestibulo-spinal asymmetry was positively related to rotational preference in experts. We suggest, that gymnasts should explore their individual rotational preference by systematically practicing different skills with a different rotation direction, bearing in mind that a clearly developed structure in rotational preference between different skills may be appropriate to develop more complex skills in gymnastics.

Network approaches for expert decisions in sports.

This paper focuses on a model comparison to explain choices based on gaze behavior via simulation procedures. We tested two classes of models, a parallel constraint satisfaction (PCS) artificial neuronal network model and an accumulator model in a handball decision-making task from a lab experiment. Both models predict action in an option-generation task in which options can be chosen from the perspective of a playmaker in handball (i.e., passing to another player or shooting at the goal). Model simulations are based on a dataset of generated options together with gaze behavior measurements from 74 expert handball players for 22 pieces of video footage. We implemented both classes of models as deterministic vs. probabilistic models including and excluding fitted parameters. Results indicated that both classes of models can fit and predict participants' initially generated options based on gaze behavior data, and that overall, the classes of models performed about equally well. Early fixations were thereby particularly predictive for choices. We conclude that the analyses of complex environments via network approaches can be successfully applied to the field of experts' decision making in sports and provide perspectives for further theoretical developments.

Evidence for the spotting hypothesis in gymnasts.

The goal of this study was to investigate the visual spotting hypothesis in 10 experts and 10 apprentices as they perform back aerial somersaults from a standing position with no preparatory jumps (short flight duration condition) and after some preparatory jumps with a flight time of 1s (long flight duration condition). Differences in gaze behavior and kinematics were expected between experts and apprentices and between experimental conditions. Gaze behavior was measured using a portable and wireless eye-tracking system in combination with a movement-analysis system. Experts exhibited a smaller landing deviation from the middle of the trampoline bed than apprentices. Experts showed higher fixation ratios during the take-off and flight phase. Experts exhibited no blinks in any of the somersaults in both conditions, whereas apprentices showed significant blink ratios in both experimental conditions. The findings suggest that gymnasts can use visual spotting during the back aerial somersault, even when the time of flight is delimited. We conclude that knowledge about gaze-movement relationships may help coaches develop specific training programs in the learning process of the back aerial somersault.

Monocular and binocular vision in the performance of a complex skill.

The goal of this study was to investigate the role of binocular and monocular vision in 16 gymnasts as they perform a handspring on vault. In particular we reasoned, if binocular visual information is eliminated while experts and apprentices perform a handspring on vault, and their performance level changes or is maintained, then such information must or must not be necessary for their best performance. If the elimination of binocular vision leads to differences in gaze behavior in either experts or apprentices, this would answer the question of an adaptive gaze behavior, and thus if this is a function of expertise level or not. Gaze behavior was measured using a portable and wireless eye-tracking system in combination with a movement-analysis system. Results revealed that gaze behavior differed between experts and apprentices in the binocular and monocular conditions. In particular, apprentices showed less fixations of longer duration in the monocular condition as compared to experts and the binocular condition. Apprentices showed longer blink duration than experts in both, the monocular and binocular conditions. Eliminating binocular vision led to a shorter repulsion phase and a longer second flight phase in apprentices. Experts exhibited no differences in phase durations between binocular and monocular conditions. Findings suggest, that experts may not rely on binocular vision when performing handsprings, and movement performance maybe influenced in apprentices when eliminating binocular vision. We conclude that knowledge about gaze-movement relationships may be beneficial for coaches when teaching the handspring on vault in gymnastics. Key pointsSkills in gymnastics are quite complex and the athlete has to meet temporal and spatial constraints to perform these skills adequately. Visual information pickup is thought to be integral in complex skill performance. However, there is no compelling evidence on the role of binocular vision in complex skill performance.The study reveals, that apprentices optimize their gaze behavior and their movement behavior when binocular vision is eliminated, whereas experts gaze behavior and movement behavior is uninfluenced by eliminating binocular vision.We state, that binocular vision is not necessary for experts to perform to their best. However, eliminating binocular vision could be part of an optimization strategy for apprentices, which could in turn be transferred to new training programs.

How do people perceive and generate options?

This chapter examines the question of how people perceive and generate options. Although most current theoretical approaches explain option perception and option generation as requiring extensive and costly cognitive processes, we will argue that people perceive their possibilities for action and generate options without such elaborate means. Borrowing from the contributions of direct perception and bounded rationality, we present and analyze data from three sports tasks: the basketball jump shot, ball allocation in handball, and trampoline somersaulting. Data from kinematics, eye-tracking, and choice behavior experiments are presented and reanalyzed to draw the parallels and distinctions between the two approaches. In conclusion, integrating research on perception, action, and cognition provides a promising description of the bidirectional link between mind and motion.

Evaluation of the tolerance and distribution of intravenously applied ferrofluid particles of 250 and 500 nm size in an animal model.

OBJECTIVE: Magnetic drug targeting may be a new method for the treatment of malignant tumors. According to the previous investigations, the success of magnetic targeting is generally contingent upon the magnetic properties and size distribution of the magnetic nanoparticles. Therefore, the aim of the present study was to verify the tolerance of two ferrofluid dispersions modified in particle size and density. MATERIALS AND METHODS: 8.75 ml ferrofluid with particle sizes of 250 or 500 nm were applied intravenously to two groups of seven New Zealand White rabbits in three doses in a time frame of 2 h. Clinical, serological,and histological evaluations were performed with regard to the tolerance of the ferrofluids. RESULTS: All animals tolerated the ferrofluid application without any clinical irregularities; there were no signs of thrombosis or embolism. Histological analysis revealed an accumulation in the liver, spleen, lung, and kidney depending on the particle size; the serological examination did not show significant alterations of the blood parameters. CONCLUSION: The ferrofluids of 250 and 500 nm particle sizes were well tolerated as shown by the laboratory and histological data and should be evaluated in further studies regarding their clinical use in magnetic drug targeting.