Preprint / Version 1

Maximizing backward somersault rotation in parallel bars


  • Hiro Hirabayashi Department of Life Sciences (Sports Sciences), Graduate School of Arts and Sciences, University of Tokyo
  • Daisuke Takeshita



Gymnastics, parallel bars, optimiziations, somersault, induced acceleration analysis


Backward somersault dismount at parallel bars in artistic gymnas- tics is considered a fundamental movement for other advanced skills, such as double backward tucked and piked somersaults. We aimed to identify strategies to maximize the number of rotations in the backward somersault dismount through computer–based optimization. We first determined the best stunt and observed hip flexion in the middle of the stunt, which is an unlikely movement for gymnasts. To study the effect of this hip flexion, we performed optimization under additional con- straints to suppress this hip flexion. Analyzing the similarities and dif- ferences between these two conditions revealed the following essential features in backward somersault dismount: 1) To increase the number of rotations, increasing the angular momentum is more effective than increasing flight time. 2) Wrist and shoulder coordination observed in both optimization conditions increased the angular momentum. 3) The hip flexion observed only in the first optimization increased the angular momentum through coordination among the wrist, shoulder, and hip joints.


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