Is there a way to set the length of the Cyclic Extrapolation in the Graph Editor? So I am trying to do a running animation for my person and I have set the key frames for beginning and end of the movement for the calf and thigh and then set the high point in the middle. I need to have it be a cycle, but not for the entire animation, only for a certain amount of time when the person then stops. Is there a way to limit the length of the cycle that is made using extrapolation, or is there some way to make that cycle for as long as its needed?

I can provide more info if needed to understand what I'm trying to do.
A cyclic extrapolation is actually driven by an F-Curve modifier. In the Graph Editor, press N to expose the Properties panel and then go to the Modifiers tab and under Cycles click Restrict Frame Range and change the End value.