Blended animation speed

Went through the tutorials (a couple of them twice). Blending is cool but the piece I cant figure out is how to change the speed at runtime with key events (I have SpeedUp and SpeedDown events bound to the letters Z and C respectively.) But have not been able to tie them into the speed variable created in the demo… Everything shown in the demo works but I cannot see where they mapped a place to change the speed (as a result it runs at full speed never going into a walk or jog).

Suggestions would be appreciated.