WHAT IS IT?
The maximum acceleration the bat experiences during the swing, measured in “g’s”. To be clear, acceleration is not how fast the bat is moving; that’s barrel speed. Acceleration determines how quickly you can reach that top speed.
More acceleration means that you can reach your max barrel speed quicker. Higher acceleration lets you wait a little longer before you decide to swing, and in some cases means that you can maintain higher bat speed for more of the swing.