Just an animation i created 
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Welcome to the forums! :D
There are a lot of ways to make blurs for speedy action, you can take the last frame and put in the next frame either between, or same position, and increase opacity, or you can add a blur of lines that zigzag, the best way to learn is to experiment and watch other animations by looking at other animator’s work and trying it out.
You should also learn how to exaggerate and choose the correct one by experimenting and practicing and practicing.
Good luck! :)