Gaming Gamecubes Capcomvssnk, how to use the groove meter, I mean com

[blackacidevil]

Its driving me nuts, im playing on AC (so i do my own moves)

i see the meter at the bottom of the screen saying A-groove FULL (jumping with lights) how the hell do i use this.

Capcom vs snk

I googled the shit out of this, I just want to know, how do i use this on AC mode (not GC)

Please