Regulation of Pendulum Length and Loading in the Backward Giant Circle in Gymnastics
Biomechanics in sports performance particularly in disciplines that
Gymnastics is one such sport that requires high musculoskeletal strength, acute proprioception and spatial awareness, coordination and balance. Many of the highly technical movements of the gymnast can be
A study performed by Sevrez, Berton, Rao and Bootsma in 2009 investigated the regulation of pendulum length and loading in the backward giant circle. The giant circle is a gymnastic element in which the gymnast departs from a handstand position above the bar and fully rotates around it backwards, without releasing the bar at any time. Study examined how elite gymnasts modify their movement patterns when performing backward giant circles on the high bar with additional weights attached at the level of the shoulders, waist and ankles.
PHYSICS BEHIND THE GIANT CIRCLE
The movement is likened to pendulum motion physics with the gymnast considered as a point mass or body centre of mass (BCM) rigidly attached to an axis of rotation. The dynamics of the pendulum movement are governed by the gravitational torque operating mgr sin (θ ) ̈where: m = gymnast body mass
g = acceleration due to gravity
r = pendulum length
(θ ) ̈= angular deviation from the vertical or handstand point
This torque results in a rotational acceleration ((θ ) ̈) modulated by the moment of inertia (I(θ ) ̈= mr2(θ ) ̈). The system can therefore be described by the following equation (θ ) ̈+ g/r sin Θ = 0 To achieve the backward giant circle energy lost to frictional forces and the conversion of energy must be overcome. The gymnast achieves this by varying her pendulum length (distance between the axis of rotation...