Author(s): GANSUKH, M., FUJIBAYASHI, N., SAKURAI, S., Institution: CHUKYO UNIVERSITY, Country: JAPAN, Abstract-ID: 1207

INTRODUCTION:
Successful landing in figure skating is essential not only for maximizing execution scores but also for preventing chronic lower-limb injuries associated with high impact forces. Toe jumps have been reported to achieve greater jump heights than Edge jumps for the same number of rotations (Sakurai et al., 1999). This suggests that differences in take-off mechanisms may lead to variations in mechanical conditions and in postural control during landing. However, the extent of influence remains unclear. Therefore, this study aimed to examine the effects of jump type and rotation number on shock absorption mechanics during landing, focusing on the Toe-loop (TL), and Loop (LP), which share the same take-off leg.
METHODS:
Ten elite female skaters performed double and triple TL and LP. Three-dimensional kinematic data were collected using a motion capture system (VICON, 200 Hz). A two-way ANOVA (jump type × rotation) was conducted. Variables included jump performance, angular momentum, COM height and vertical velocity at initial contact, trunk and lower-limb joint flexion angles, during landing.
RESULTS:
Jump Performance: Flight time showed significant main effects of jump type and rotation, with TL demonstrating longer flight times than LP. COM vertical displacement increased with rotation. Jump distance showed a significant main effect of jump type, with TL greater than LP. Initial Contact: Significant interaction effects were observed for trunk and hip flexion angles. With increasing rotation, the trunk became more upright and hip flexion increased, particularly in LP. Angular momentum was greater in LP. A main effect of rotation was observed for all variables except ankle joint angle. Maximum values during landing: An interaction effect was observed for trunk flexion angle, with LP showing a greater increase in flexion as rotation increased. Rotation influenced joint and trunk flexion during landing.
CONCLUSION:
Jump performance primarily varied according to the main effects of jump type and rotation, whereas landing posture is influenced by both factors. TL exhibited longer flight times, whereas LP landed with greater angular momentum. Although the flight time increased with increasing rotation in both jumps, the time available for landing preparation remained limited. As a result, lower-limb joints tended to land in a more flexed posture. In addition, the maximum flexion angle after contact increased, suggesting that the mechanical demand during landing was elevated. These characteristics partially coincide with the shock absorption pattern observed in “hard landing” in multi-revolution jumps reported by Lockwood et al. (1997). In particular, in LP, which was characterized by shorter flight time, the hip joint was required to land in a more flexed position, suggesting that a shock absorption strategy involving not only the lower-limb joints but also the trunk may have been employed.
REFERENCES:
Sakurai et al., ISBS Proc., 1999
Lockwood et al., Clin. Biomech., 1997