^ ^ ^ ^ you should post these so it's easier to see immediate problems with your animation.
I stabilized your guy a bit. The character shouldn't be jumping around during a run cycle. The forward movement is handled by your code.
^ ^ This is what your animation actually would look like with only up and down movement of the torso. Not half bad
Not sure if your trying to force the animation to 4 frames. If you are I would change up the last frame. The transition from the 3rd to 4th frame makes a rough 'jump'. The 'jump' makes it look more like a gallop than a run which you can totally go for if that's what you want. A lot of people go for the gallop
*note if your click/shift-click an image it will grow/shrink.