Eccentric strength and postural perturbations following gymnastic landings

Introduction: Successful landing performance in artistic gymnastics requires effective attenuation of impact forces while maintaining postural stability. Adequate lower-limb muscle strength is considered important for both performance and injury prevention, while dynamic stabilization represents one of the key determinants of successful landing execution in gymnastics (Kyselovičová et al., 2023; Moeskops et al., 2019). Despite the recognized importance of eccentric muscle function during landing, evidence regarding the relationship between lower-limb strength and objective measures of landing stabilization remains limited (Pavlasová et al., 2025). Therefore, the aim of this study was to determine whether eccentric lower-limb strength is associated differently with Dynamic Stability Index (DSI) and Time to Stabilization (TTS) during gymnastic landings.Methods: Seventeen female artistic gymnasts (14.4 ± 1.9 years) performed four landing tasks representing different levels of motor complexity: a drop landing from a 30-cm platform, a forward somersault, a backward somersault, and an acrobatic series consisting of a round-off, optional back handspring, and backward somersault. The study was approved by the Ethics Committee of the Faculty of Physical Culture, Palacký University Olomouc, and written informed consent was obtained from all participants and their legal guardians. Postural stabilization was assessed using an inertial sensor (Delsys Inc., USA) positioned at the level of the fourth lumbar vertebra. Ground contact was identified using peak vertical acceleration, and lower-back angular velocity signals were filtered using a 4th-order bidirectional Butterworth filter (30 Hz) prior to calculating DSI and TTS for the sagittal and frontal planes during both 1-s and 3-s intervals following landing according to published methods (Colby et al., 1999; Fransz et al., 2015; Wikstrom et al., 2005). Eccentric strength of the dominant lower limb was evaluated using an IsoMed 2000 dynamometer (D. & R. Ferstl GmbH, Germany). Isolated eccentric ankle dorsiflexion, knee flexion, and hip flexion were tested at 180°·s⁻¹. Peak torque (PT) and work (W) were calculated from the isokinetic phase of movement and normalized to body mass. Multivariate multiple regression analysis was performed to investigate associations between eccentric strength variables and postural stabilization outcomes.Results: Significant associations were identified exclusively for DSI variables, whereas no significant regression models were observed for TTS. Similarly, all significant findings were limited to the sagittal plane. The strongest relationships were observed during backward somersault landings. Higher ankle PT was associated with greater sagittal DSI during the 3 s interval (β = 2.11, p = 0.037), whereas ankle work demonstrated an opposite association (β = −1.69, p = 0.025). Similar patterns were observed for hip musculature. Hip PT was positively associated with sagittal DSI during both the 3 s interval (β = 1.60, p = 0.015) and the 1 s interval (β = 1.97, p = 0.003), while hip work was negatively associated with DSI during the 3 s interval (β = −1.57, p = 0.016) and the 1 s interval (β = −1.81, p = 0.004). No significant associations were identified for knee flexor strength.Conclusions: Eccentric lower-limb strength appears to be associated with the magnitude of postural perturbations following landing rather than the time required to regain stability. The absence of significant relationships with time to stabilization suggests that stabilization duration may depend more strongly on sensorimotor control than on isolated muscle strength. Furthermore, peak torque and work demonstrated consistently opposite associations with dynamic stability, indicating that maximal force production and sustained force-generating capacity may represent distinct neuromuscular contributions to landing control. Significant relationships were observed primarily for ankle and hip musculature, highlighting the importance of distal and proximal stabilization mechanisms during gymnastic landings.Acknowledgements: This study was supported by the Internal Grant Agency of Palacký University Olomouc (IGA_FTK_2024_007).