Started with exposure to something meant to give normal folks superspeed. I don't actually know exactly the specific details. I was too much Impulse at the time to not be bored with the explanations. Sorry.

[And he does regret that. He's never really had the time or place to study the specifics. And the prospects of being a lab subject ever again aren't really on his agenda.]

Look, I don't know what to tell you. This is just...a part of me. One, to be honest, I mostly ignore unless the situation is right. It just isn't...well, you know how dangerous the speed force is. How few people survive it for any length of time.