Author(s): PAVLASOVÁ, K., BIZOVSKÁ, L., JANURA, M., Institution: PALACKY UNIVERSITY OLOMOUC, FACULTY OF PHYSICAL CULTURE, Country: CZECH REPUBLIC, Abstract-ID: 289

INTRODUCTION:
A controlled landing after an acrobatic element or acrobatic series is essential for achieving high scores and ensuring gymnast’s safety (1). Key factors include precise timing and appropriate levels of muscle activation (2), which optimize lower-limb joint stiffness before impact and facilitate deceleration upon contact with the ground (3). Muscle activity during landing varies depending on the preceding motor task (4), making optimal activation crucial not only for successful performance, but also for reducing injury risk (1). Therefore, the aim of the study was to assess the effect of the acrobatic element on postural stabilization and lower-limb muscle activity during landing.
METHODS:
Eighteen female gymnasts participated in the study. Landing stabilization was assessed using time to stabilization (TTS) during the first second after contact based on lower-back inertial sensor data. Surface electromyography evaluated gastrocnemius medialis (GM), tibialis anterior (TA), and peroneus longus (PL) activity within ±300 ms of contact. Gymnasts performed three valid forward somersaults (SF), backward somersaults (SB), and acrobatic series (AS). Data were analysed using one-way repeated-measures ANOVA with paired t-tests, and stabilization indices were evaluated using Friedman ANOVA (α = 0.05).
RESULTS:
Significant differences in time to stabilization were found across acrobatic tasks in the vertical (p < 0.001), anteroposterior (p = 0.008), and sagittal plane (p < 0.001). Pairwise comparisons revealed differences between AS and SF in the sagittal plane, AS and SB in the vertical and anteroposterior directions, and between SF and SB in the anteroposterior direction and sagittal plane.
Muscle activity comparisons showed higher pre-contact GM activity in SF than in AS and SB, higher post-contact TA activity in SF than in AS, and higher pre-contact PL activity in SF than in AS.
CONCLUSION:
The results showed that time to stabilization during landing varied depending on the type of acrobatic task, along with differences in muscle activity. Landings after AS were generally stabilized faster than those after isolated elements, which may be due to higher jump height and the possibility of proper preparation and control during landing. In contrast, SB may result in incomplete rotations and reduced landing stabilization due to lower jump height. SF appeared to be the most demanding for landing, likely because of the absence of visual feedback and limited ability to anticipate the landing.

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4) Wang X, Zhang S, Fu W, J. of Human Kin., 2017