Energy and structure are interdependent at every level. When you have more ability to do things, the body does things- because that's what life does. Hysteresis (biological inertia) and resonance govern life's inherent ability to become more elegant, when it has the chance. The chief product of a decrease in cellular energy is growth (both hyperplasia and hypertrophy). The chief product of an increase in cellular energy is transformation.
A literal example is the shift from larval hormone to molting hormone in insects. You can either continue to be a caterpillar or you can metamorphosize into a moth. I bet you thought I was going to say 'butterfly.' Butterflies are savage, vile creatures.