Ok so i have a few tips for you, if you want to animate smoother, get a decent image of a run cycle from google would be the first bit of advice.
next, you want to make key frames first.
- springing into the run
- both feet off the ground
- front foot hitting the floor
- and absorbing the step
once you have these key frames you can then put in more frames to smooth the transition
here is an example
visualize this for all angles.
also a tip to remember is the movement of the persons arms, arms and legs move in opposites so if the left leg is the forward leg, then the right arm will be forward, but if the right leg is forward the left arm will be forward.
hope this helps