Incorrect - there is no enduring energy storage in a bent leg. There is a very brief storage, but only on the order of "bounce" duration.

Ordinarily, if your leg is bent you must have either converted your potential energy to kinetic energy, or else lost it. If you don't plan on converting potential energy to kinetic, don't bend your knee. If you only plan on converting a little bit of energy, only bend your knee a little bit...