The Role of Shoulder and Hip Torques Generated during a Backward Giant Swing on Rings

• Published in: Journal of applied biomechanics 2000-08, Vol.16 (3), p.289-300
• Main Authors: Sprigings, Eric J., Lanovaz, Joel L., Russell, Keith W.
• Format: Article
• Language: English
• Subjects: Computer simulation
• ISSN: 1065-8483; 1543-2688
• DOI: 10.1123/jab.16.3.289

Backward giant swings on rings were performed by 2 elite gymnasts from both a stationary and a swinging handstand position. One of the ring cables was instrumented so that tension values could be recorded. Muscle torques and corresponding power profiles for the hip and shoulder joints were calculated and used to interpret the movement patterns displayed by the gymnasts. The hip-flexors played a primary role in preventing excessive hyper-extension of the hip joint during the downward swing. Overall, during the backward giant swing, the hip-joint flexors/extensors acted as a net energy sink for the system rather than as a source of energy generation. The piking motion that was observed to take place just past the bottom of the swing was primarily due to the momentum built up in the legs during the rapid straightening of the body during the bottom of the swing. The shoulder flexors/extensors functioned as the primary source of energy generation to the system. From a swinging handstand, with an initial handstand swing amplitude of 16°, the gymnasts were able to arrive at the next handstand position with approximately 6–7.5° of residual swing, which was close to the optimal value of 4° predicted by computer simulation.