You can find out more about Matt Whiteside and All-Star Performance at http://all-starperformance.net.
A good way to learn the routine of a good pre-game bullpen session is to get to a major league or AAA game a little early. Carefully watch the pitcher and catcher work the bullpen session. Count the pitches and pitch types. Are they off the windup or stretch?
Matt’s rule thumb for pitch limits and bullpen sessions is great:
Pitch limit = 5 times pitchers age (I think this only works for kids though, because Matt is 38, and I don’t think he’s ready to throw 190 pitches).
Bullpen session = 1/2 of pitch limit.
So, for a 15 year old player - a 75 pitch limit and 35-40 pitch bullpen sessions make sense.
You can learn more about the Double Goal Coach at http://positivecoach.org. You can order the book from that website, or it is usually carried at Borders.