Author(s): SHIMIZU, K., KANKE, S., SASAKI, R., Institution: KEIO UNIVERSITY, Country: JAPAN, Abstract-ID: 1570

INTRODUCTION:
Rhythmic gymnastics is an esthetic sport that emphasizes the elegance of movement and the precision of technique, evaluated and scored based on established criteria. One crucial aspect of performance is the “Difficulty Body", comprising elements, such as jumps, balance, and rotation1). In this study, we focused on the "split leap" which is frequently used in the performance structure at all age-groups2). We aimed to delineate the distinctive features of this movement by comparing its execution among gymnasts of varying competition levels, as well as to explore the movement methods that are highly evaluated.
METHODS:
Six rhythmic gymnasts(20.7±1.4yrs, BMI 18.9±1.1) participated in this study, and performed split leap jump and two static anteroposterior leg-opening positions, one with pelvic rotation suppression and the other without. The angle of the hip joint and pelvic rotation in split leap and two static positions, and changing of angular velocity of hip joint during jump were measured. These measurements were compared based on the competition level of the participants. Furthermore, the jump movements were evaluated by internationally qualified judges, and these evaluations were compared with the measurement values obtained.
RESULTS:
The results showed that the angle of the hip joint with pelvic rotation was the largest in the static condition without pelvic rotation suppression compared to the other static condition and split leap jump. Among the jumping movements, the more skilled participants maintained a larger angle during jumping, maintaining approximately 90% of the maximum split angle for 21% of the leap time. Notably, the angular velocity of the swinging leg exhibited a movement pattern that facilitated the maintenance of the large split angle. These movement characteristics were deemed to meet some of the high evaluation criteria set by judges.
CONCLUSION:
The study suggested that jumps receiving high evaluations from judges necessitated maintaining a significant split angle above the default leg angle for an extended duration, with variations noted according to the competition level. While the indicators used in this study can be explained by the judges evaluation criteria, additional factors should also be considered.
REFERENCES:
1) Federation International de Gymnastique, 2022–2024 CODE of POINTS Rhythmic Gymnastics.
2) Niwa et al., The Relation between the Leg Split Angle and Flexibility for the Split Leap. Bulletin of Sendai College, 2005. 36(2): p.32-39.