Forward Somersault Research Articles

Effect of Ability on Twisting Techniques in Forward Somersaults on the Trampoline

This study was designed to investigate the effect of ability on technique in the forward somersault with half twist (Barani) and the forward somersault with one and one half twists (Rudi) on the trampoline. Eleven trampolinists ranging in ability from elite (national representative) to early intermediate (regional representative) were analyzed using three-dimensional analysis techniques. Cumulative twist angle, rate of twist, angle of tilt of the twist axis, chest rotation, hip angle, and hip lateral flexion angle were measured. Characteristics of the arm actions were also assessed using an internal frame of reference. To generate twist in the Baranis, trampolinists tilted the axis between 5° and 14°; the amount of tilt was inversely related to ability (p < .05). In the Rudis, subjects tilted the axis between 15° and 23° using more asymmetrical arm actions and larger and more rapid hip extensions, hip lateral flexions, and chest rotations than in the Baranis. The timing and magnitude of the actions differed among the subjects and were related to ability.

How do elite trampolinists perform twisting forward somersaults?

How do elite trampolinists perform twisting forward somersaults?

How do somersaulters land on their feet?

Body movements of trampolinists landing upright from forward somersaults, with eyes open and closed, were analyzed to test a theory of how braking and timing of actions are conjointly controlled. In regulating landing, rotation has to be slowed by extending the body so that it reaches the upright just as the feet hit the trampoline. Extending a theory of visual control of linear braking, it was hypothesized that upright landing is achieved by perceptually regulating body extension so as to keep the ratio angle of body to upright: rate of change of angle (the tau function of the angle) proportional to time-to-landing. The data support the hypothesis, indicate that vision improves precision of control, and argue further for the value of the tau function in the perceptual regulation of action.

External Cephalic Version at Term. A Randomized Controlled Trial Using Tocolysis

Objective To assess the role of external cephalic version (ECV) at term, using tocolysis. Design A randomized controlled trial over a 12 month period. Setting Harare Maternity Hospital, Harare, Zimbabwe. Subjects 208 women with breech presentation at term were recruited after satisfying eligibility criteria. There were 103 women in the study group and 105 in the control group. At the end of the study a further 104 women were recruited for ECV. Intervention ECV attempted after intravenous injection of 10 micrograms of hexaprenaline, using either forward or backward somersault over a maximum period of 5 min. Main outcome measures Success rate in terms of presentation during labour, need for caesarean section, and various variables related to fetal outcome. Results ECV reduced the frequency of breech presentation during labour from 83% to 17% and that of caesarean section from 33% to 13%. There were no troublesome complications from the procedure. Conclusion In carefully selected women with breech presentation, ECV at term using tocolysis, safely reduced the rate of breech presentation in labour and also the caesarean section rate. Further research is needed to determine the role of ECV in early labour.

Biomechanical Analysis of the Developments for Forward Handspring, Followed by a Stretched Forward Somersault on the Floor

There are three basic types of forward handspring, followed by a forward somersaults that are performed on the floor, a forward handspring followed by a tucked forward somersault, a forward handspring followed by a piked forward somersault and a forward handspring followed by a stretched forward somersault. They are different forms of movements in the second position from forward handspring as first position. Each forward handspring, followed by forward somersaults are a composite movement consisting of a forward handspring and a forward somersault. The forward handspring, followed by a tucked forward somersaut develops into a forward handspring, followed by a piked forward somersault, and they develop into a forward handspring, followed by a stretched forward somersault: the basis for these basic movements.This study attempts to determine the technical points of difference in the three basic types of forward handspring, followed by a forward somersault and to determine an efficient take-off for the forward somersaults develops into a stretched forward somersault. Althought the first part is technically similar there are differences in the take-offs due to the differences in the second part. In the landing from the forward handspring for a forward somersault in the first part when the heels and toes touch the floor the forward somersault is performed by bending the body backwards, leaping from a backward falling posture into th preparation for the leap. From this posture the spring is performed by returning the backward bending upper body toward the position which completes the leap. The motion here resembles the rebound of a bow, with the legs hitting the floor.This enables the upward leap and subsequent forward rotation for the forward somersalt in second part. In a forward handspring follwed by a stretched forward somersault, the differences are mainly in the utilization of the efficiency of rotation after the take-off from the other two types. And, the differences are in the leap into the forward somersault in the second part and the movement of the upper body to assist the leap by using the legs.

The simulation of aerial movement—I. The determination of orientation angles from film data

Quantitative mechanical analyses of human movement require the time histories of the angles which specify body configuration and orientation. When these angles are obtained from a filmed performance they may be used to evaluate the accuracy of a simulation model. This paper presents a method of determining orientation angles and their rates of change from film data. The stages used comprise the synchronization of data obtained from two camera views, the determination of three-dimensional coordinates of joint centres, the calculation of an angle from a sequence of sine and cosine values and the curve fitting of angles using quintic splines. For each state, other possible approaches are discussed. Original procedures are presented for obtaining individual error estimates of both the film data and the calculated angles to permit the automatic fitting of quintic splines for interpolation and differentiation and for deriving the time history of an angle as a continuous function from a sequence of sine and cosine values. The method is applied to a forward somersault with 1 1 2 twists and the average error estimate of 17 orientation angles is obtained as 2.1 degrees.

Critical Examination of Ground Reaction Force in the Running Forward Somersault

Ground reaction forces (GRF) elicited by nine male gymnasts during a running forward somersault were examined to investigate their characteristics in relation to the performance. Support averaged 135 ms with braking GRF dominating in the antero-posterior direction. Vertically, impact averaging 13.6 body weights (BW) was recorded followed by a second peak of 6.1 BW. The relative minimum in vertical GRF and lowest body position coincided temporally at 23% of support time; maximum knee flexion and minimum distance between the center of gravity (CG) and the support point occurred at 36 and 37%, respectively; and the second vertical GRF peak and maximum dorsiflexion were registered at 44%. The results suggested that, while vertical touchdown and last contact velocities of the CG could be approximated from GRF, eccentric ankle and knee extensor contraction continues beyond the relative minimum in the vertical GRF curve and is more closely related to the period before the CG reaches its minimum distance from the support point.

The Cocoon of the Honey Bee, Apis mellifera L.

AbstractDuring cocoon construction the predominant movement made by larvae of the three honey bee castes is a forward somersault which is made dorsal side outermost. Worker, drone, and queen larvae complete one somersault in 52, 46 or 67 (at two different times), and 32 minutes respectively with the total number of somersaults made during cocoon construction being 27-37, 40-50, and 40-80 respectively; the larvae take 37, 54, and 30 hours respectively to complete their cocoons. Weight changes of larvae before and after the cocoons are made are given.Worker and drone larvae build completely enclosed cocoons directly on the side walls and end walls of cells, but queen larvae leave spaces between the cappings and the cocoons and do not cover the bases of their cells with cocoon material.Cocoons consist of silk gland secretion (in thin sheets and threads), a colourless material, a light yellow material, and a more solid brown material (faeces); the last three are discharged from the larval anus. When, how, and where these various secretions and excretions are placed in the cocoon, and their probable origins, are described. Possibly some brood food is incorporated into the cocoon but skin secretions or larval blood are not.