First I'll credit some of this response to the great Vince Anderson, whom I had the pleasure to learn from about the biomechanics of track athletes.
Sprinters and distance runners should have nearly the same motions. The aggressiveness of the knees and arms is lessened, but the general concept stays the same. Knees together when the foot hits the ground. Hands in your pockets. Quick recovery. Etc.
Don't think about picking your knees up. Stand in place and drive your knees. Do you move forward? Maybe a bit. Reverse the thinking in a way. DRIVE your foot into the ground. The force you generate from the downward motion is what moves you. The knee driving upwards is a reactionary motion to the force put into the ground. Upright posture, keep your chin level, shoulders down.
All distance runners I've coached have a "tell" so to say, when they're clearly beginning to tighten up. Some do a weird deal with their hands, some tilt their head to the side, some raise their shoulders, etc. Watch Usain Bolt or Carl Lewis run. HUGE range of motion (big shapes) and at the same time, relaxed. There is much to be learned from other event areas in the distance events.
Lastly, your glutes are key. Most distance runners don't ever work on them. Getting your feet back down to the ground is essential. Speeding that motion up requires strong posterior chain development. Hope this helps,