RUNNING APPROACH VELOCITY AND ENERGY TRANSFORMATION IN DIFFICULT VAULTS IN GYMNASTICS

  • Klaus Knoll
  • Jürgen Krug
  • Hans-Dieter Zocher
Keywords: kinematography, speedography, energy, angular momentum, gymnastics

Abstract

Introduction: Running approach velocity is the most important phase of energy production in gymnastic vaults. The take-off from a springboard and the push-off from a vaulting horse are phases of energy transformation. Difficult vaults in gymnastics can be characterized by a high and wide second flight phase. In this phase rapid airborne rotations are performed. These difficult saltos demand an appropriate level of translational impulse and angular momentum. Methods: A special measuring system wasused with two 50 Hz video cameras connected by genlock. Running approach velocity was measured with a laser velocity system. Additionally, the vault was recorded with a high speed video system (500 Hz). This setup was applied at the 1997 World Gymnastics Championships in Lausanne. Results: About 300 running approach velocities for different vaults were analyzed. The highest speed was 8.9 m/s in the men’s competition and 7.9 m/s in the women’s competition. The male gymnasts reached approximately 1 m/s higher running approach velocity than female gymnasts. The highest flight was 3 m over the mat. These parameters were measured in handspring vaults. With round off entry vaults (Yurchenko) the running approach velocity and the heights of the second flight phase were slightly lower. Conclusions: The investigations during the 1997 World Gymnastics Championships prove that the greatest difficulties also demand the highest levels of running approach velocity. Concerning the take-off it is interesting to note that after contact with the springboard the knee and hip joints were fixed. Therefore, the take-off from the elastic springboard is more a tension-shortening cycle than a stretchshortening cycle. The first flight phase is very low but with a high level of angular momentum. The transformation index of the energy and angular momentum from the first flight phase to the second flight phase proves that both parameters have decreased. The extensive databases make it possible to recommend training programs for the FIG. In addition to that, recommendations were made for the new point code. This point code will be valid after the 2000 Olympic Games. References: Brueggemann, G.-P. (1994). Biomechanics of Gymnastic Techniques. Sport Science Review, Champaign, 3, 2, 79-120. Komi, P.V. (1992). Stretch-shortening cycle. In Komi, P.V. (Ed.). The encyclopaedia of sports medicine. Vol. III: Strength and power in sport. Oxford, UK: Blackwall Scientific, 169-179. Krug, J. & Noble, L. (1997). Application for Participation in the 1997-98 ISBS Gymnastics Project. Fig. 1: Measuring System