Balancing on airby
johnmComment by graphicfunk: The swing requires more balance than it is attributed it. Of course, we get use to it pretty quick and then dismiss the dexterity, but it entails balance all the same.
I was impressed with this picture not only because you captured the apex of the swing, but because you employed the silhoette technique.
There are ways to make this image more compelling, yet what follows are only suggestions, because your image is very convincing as is.
Look at the image carefully and you will observe that a scanty hint of the ground is present. Also, a scant amount of the swing mechanism. So one way is to crop our the land artifacts along with the swing stands. This leaves just the figure and the sky. Since this is advance editing you can now concentrate on the sky by selecting the figure and then inverting. You then pump up the contrast of the sky and then dodge and burn in promising areas. Another approach is to use the elliptical tool and create an ellipse around the figure, invert and then darken the surrounding area. However, first take care that you have increased the contrast on the sky inside the ellipse.
Outside of this you have a good compositional style and you think out your ideas. In competition it is hard to present an absract equivalent of the challenge's meaning. It is all dependent on voter reaction and some just simply miss the point. After all, the subject of physics eludes a lot of people.
Photographer found comment helpful.