I stumbled upon this article recently about running form and it really hit the nail on the head. I’m pretty sure I do this…
The ground is very tempting. Your foot wants to hang out there a while. To the beginner it seems (unconsciously) a little easier to land — pause — and then push off than to essentially refuse the ground’s embrace — to strike it, thrust it away, be done with it. But that extra investment of effort up front saves energy in the long run. Most runners make little progress in overcoming their laziness. Those who make the most progress become the best runners.
Be sure to read the whole article, the last bit is the best. And it was written by Matt Fitzgerald. I got my Ironman Training Plan from his book!