Do this exercise but mimic a true running motion. As you're bringing the knee from the back to the front do not keep it up so high. Keep it a bit away from your hip to the floor then as you're bringing foot back from the front to the back let it just skim the ground as if you're mimicking a true running motion like you're running on air
This exercise would be better suited to throwing if the throwers arm was supinated before being pronated as stress is reduced on the inner part of the elbow. Try it out and you will see: (1) You obtain additional throwing power by activating the biceps muscle as you supinate the wrist and (2) As the arm moves forward, the wrist goes from supinated to pronated, which provides rotational angular momentum to the throw. In a nutshell: Going from supination to pronation as the arm moves forward offers more throwing power with less strain on the inner elbow (Tommy John ligament).