Dancing with Gravity: The Human Body Blade

Figure 9.3.  Comparative examples of retaining proper shape under stress:  (1) oscillating elastic ruler; and (2) inverted phase of a Backward Handspring.

FUNDAMENTAL TUMBLING CONCEPTS

1.  Dynamic Tension

     Tumbling not only involves moving into and out of specifically timed body shapes in the skill series, but also requires maintaining an active (dynamic) tension in the muscles on both sides of the body to render a quasi-elastic property of the total body unit.  To develop the concept, example 1 in figure 9.3 illustrates the reaction of an elastic ruler when held vertically at one end and moved quickly back and forth.  Observe its reactionary bowing, a bending under tension- precisely what the gymnast should attempt to achieve throughout a tumbling sequence.

     In example 2, note the shape similarity between an oscillating ruler and a gymnast during the inverted phase of a Backward Handspring.  The idea here is to maintain a dynamic tension throughout the body as it moves through its intended shapes.  Establishing active muscle tension on both sides of the body provides for more efficient momentum transfers, improves movement time within and between each skill, and renders an all-around smoother flow throughout the tumbling performance.
-Pg 197, Championship Gymnastics, by Gerald S. George, Ph.D.

When I think of uniformed hollow-arch shapes, the body blade device comes to mind:







I set one of these up before as an experiment, maybe 2 summers ago, using the men's cross-machine rings:


 Here's another tutorial on how to set one up.

Related:
Standing hollow
Hollow to tight arch