Transition animations problem

I'm in the process of animating a 2D character, however, transition animations such as stopping after running are giving me headache.

What would be the best way to handle such animations? For example, I would like to play an animation when the character starts running, loop a run cycle as long as the character is running and when the character stops running, play a stopping animation.

 

Use a speed parameter similar to how Unity training material shows examples of. A stopping animation is not needed, but a idle animation will be needed.
https://unity3d.com/learn/tutorials/topics/2d-game-creation/2d-character-controllers?playlist=17093