A cinematographical analysis of twisting about the longitudinal axis when performers are free of support

Abstract

Purpose: The purpose of this study was to analyze and compare the variables associated with man's ability to rotate about the longitudinal axis once free of support with and without prior transverse rotation. Procedure: The subjects were three skilled University of Texas drivers. Each of the divers had earned international recognition in diving competition. The divers performed seven different tests from the seven and one-half meter platform at The University of Texas at Austin. Each test was performed with the legs taped together. Test four was performed with the arms tapped to the sides of the subjects, but in all other tests, the arms were free to attempt to twist the body. Test one was a feet first jump, two was a back layout somersault, three was a feet-first pike jump, four was a feet-first pike jump with arms taped, five was a front layout dive, six was a front pike somersault, and seven was a front one-and-one half pike somersault. Two cameras were used simultaneously; one was located 91 feet 7 inches in front of the platform, and the other was 62 feet at a right angle from the platform. The frontal camera was a 16mm Bolex spring wind camera equipped with a zoom lense and operating at 62 frames per second. The right angle camera was a 16mm Bell and Howell electric camera equipped with a zoom lense and operating at 65 frames per second. A Vanguard Motion Analyzer was used for film analysis..