As it refers to a sprint?

The rate of change of acceleration with respect to time. Commonly called jerk in physics.
In other words, acceleration is the rate of change in your speed, snap/jerk is the rate of change in your acceleration.

Perfect. Thank you.

ya, the week after Newton came up with the second law of motion, F=ma, he published a little known work on "snap". few know about it.

I hear it's a very derivitive work...

You've completely killed this thread with your precise and very helpful answer.

Shame on you.