As an art director, I would try the headline right in the very, very center of the frame – which would end up just below the vertical body line and in that solid blue area. The photo works and everything is great, but the message is a little lost in the area below. I know it's nicer there for art, but the bottom line is selling shoes. Placing it in the center allows everything else to revolve around the message in a bulls-eye pattern. And then the Puma logo needs to be relocated after to compliment and brand.
Is "Defy Physics" a current message vehicle from a shoe company? If it's yours, it's much better. 'Gravity is Nothing' is a statement on something being empty. 'Defy' is a action command that appeals to X and Y Gens or anyone young.