The effect of expertise on postural control in elite sport ju-jitsu athletes

Anna Akbaş; Wojciech Marszałek; Sławomir Drozd; Wojciech Czarny; Paweł Król; Krzysztof Warchoł; Kajetan J Słomka; Marian Rzepko

doi:10.1186/s13102-022-00477-3

The effect of expertise on postural control in elite sport ju-jitsu athletes

BMC Sports Sci Med Rehabil. 2022 May 13;14(1):86. doi: 10.1186/s13102-022-00477-3.

Authors

Anna Akbaş¹, Wojciech Marszałek², Sławomir Drozd³, Wojciech Czarny³, Paweł Król³, Krzysztof Warchoł³, Kajetan J Słomka², Marian Rzepko³

Affiliations

¹ Department of Motor Human Behavior, Institute of Sport Sciences, Academy of Physical Education, 72a Mikołowska Str., 40-065, Katowice, Poland. a.akbas@awf.katowice.pl.
² Department of Motor Human Behavior, Institute of Sport Sciences, Academy of Physical Education, 72a Mikołowska Str., 40-065, Katowice, Poland.
³ Institute of Physical Culture, University of Rzeszów, 16c Aleja Rejtana Str., 35-959, Rzeszów, Poland.

Abstract

Background: Due to the high postural control demands of sport ju-jitsu, it is likely that long-term sport ju-jitsu training may induce sport-specific adaptations in postural control, especially in positions directly related to combat. The aim of the study was to assess the differences in postural control between elite sport ju-jitsu athletes and untrained controls in non-ecological and ecological conditions and to investigate the relative contribution of spinal and supraspinal mechanisms to postural control in expert athletes.

Methods: The study was conducted on eleven male elite ju-jitsu athletes and ten non-athletes. The data was collected with the use of a force plate under two conditions: quiet standing and ju-jitsu combat stance. Apart from the standard analysis of the spatial-temporal parameters of center of foot pressure, non-linear measures were used, namely rambling-trembling and sample entropy. The non-parametric Mann-Whitney U test was used to compare both groups.

Results: The main findings of the study showed that in quiet standing, elite ju-jitsu athletes and non-athletes had comparable postural control in both the anterior-posterior and mediolateral planes. In contrast, in the combat stance, elite athletes had lower values of postural sway and rambling component (range and rms) and higher values of sample entropy in comparison to the non-athletes (p < 0.05). No differences were found in the trembling component of sway between groups in the combat stance (p < 0.05).

Conclusions: Smaller postural sway and its rambling component in sport ju-jitsu athletes may indicate the more precise control of center of foot pressure and improved ability in estimating its position. The sample entropy results confirmed that the displacement of center of foot pressure for sport ju-jitsu athletes was more irregular, which demonstrates greater automatization in postural control. The results also confirm the importance of ecological validity in investigating postural adaptations associated with sports expertise.

Keywords: Ecological conditions; Equilibrium; Rambling-trembling; Sample entropy.