What governs successful performance of a complex whole body movement: The Kovacs release-regrasp on horizontal bar?

Abstract

The Kovacs is a release and regrasp skill performed on the horizontal bar in men's artistic gymnastics. It is a popular skill in elite competitive gymnastics with over 40% of male gymnasts performing a variation of the Kovacs at the London 2012 Olympics. In the qualifying competition 84% of Kovacs were successfully regrasped, with the remaining 16% resulting in a fall. The aim of the present study was to determine why some gymnasts are more successful than others at regrasping the bar, with a secondary aim to determine how a less successful gymnast could alter his technique in order to become more successful. Nine performances of the Kovacs by each of two gymnasts, one 100% successful and one 11% successful, were analysed to determine differences in release and regrasp parameters. The technique of the less successful gymnast was optimised using a computer simulation model to increase the percentage of catches (success rate). The successful gymnast had larger and more consistent release windows and a radial velocity towards the bar at regrasp. The less successful gymnast had higher horizontal velocity at release and a mean radial velocity away from the bar at regrasp. Optimising his simulated technique increased the rate of success from 11% to 93%. The actions prior to release were performed earlier than in the recorded performances leading to a more vertical path of the mass centre at release and a radial velocity towards the bar at regrasp.

The limits of aerial and contact techniques for producing twist in reverse 1½ somersault dives

“…In each of the five limiting dives there was some margin to allow compensation for variation in execution as indicated by the amounts of additional arm abduction available in the twisting phase (ranging from 8° to 23°). In order to assess how much margin for compensation might be needed the start times and durations of joint angle changes, in the production of tilt and twist for the third case of arm asymmetry in which 5½ twists were produced, were each perturbed by 0.01 s Hiley & Yeadon, 2016a, 2016b to determine the effect on somersault and twist. In the perturbed simulations there was a range of 7% in twist at 0.75 s and 1% in somersault.…”

“…In any performance of a given movement there will be variability in execution (van Beers, Haggard & Wolpert, 2004) and so any theoretical optimisation should take such variability into account as in, for example, . Studies using repeated trials to determine variability in elite performances of whole body movements have found coordination timing precision mean values of between 8 ms and 12 ms (Hiley, Zuevsky & Yeadon, 2013;Hiley & Yeadon, 2016a, 2016b. In any viable limiting movement there would need to be sufficient flexibility to accommodate timing variations of the order of 10 ms.…”

Еxploration on Salto “Jaeger” Piked to Hang on Uneven Bars

“…To increase the technical level and effectiveness of the performances, researchers by tradition focus their scientific interest on studying various biomechanical characteristics and technical peculiarities of the elements. The scope of analyses includes elements such as: Kolman and Pegan (Čuk, 1995); Gaylord (McLaughlin et al, 1995); Tkachev (Holvoet et al, 2002;Čuk et al, 2009;Hiley et al, 2007;Naundorf et al, 2012, Hiley, Yeadon, 2012, Spencer, Schuhmann, 2017; Gienger (Potop et al, 2015); Kovacs (Hiley, Yeadon, 2016). The element Jaeger salto, whose performance technique is the object of analysis in the present research, is also very interesting.…”

A Review of Forward-Dynamics Simulation Models for Predicting Optimal Technique in Maximal Effort Sporting Movements

“…The movement solution deemed optimal was the one which maximized success within this noisy environment. A similar approach has subsequently been used to quantify the margin for error in movement timing [152,153], as well as the effect of constraints such as strength and variability on margin for error [154]. Applying this approach to muscle or torque actuator activation timings could enable inherent movement variability to be included within the optimization process of muscle-driven and torque-driven forward-dynamics simulation models of maximum effort sporting movements [124].…”