For some of the training modes you can pause the game and it doesn't effect your time or score in any way. When you are doing the punch combo training session it make it easier to write down what punches you just did by pausing the game first. That way if you forget what punch comes next just pause the game and look what you wrote.
This trick works on the other training session where the trainer tells you what punch he wants you to throw. Most of the time when you pause it before he speaks the audio will carry over even though you paused. Which makes it a lot easier to quickly unpause when you are ready and throw that punch.
Look Ma No Hands Punch: Defeat Roy Jones Jr.
Watch the Birdie: Defeat Bernard Hopkins.
Bolo Punch: Defeat Ray Leonard.
Lunging Hook Special Punch: Defeat Evander Holyfield.
Ducking Hook Punch: Defeat Muhammad Ali.
Highlight Play Now at the main menu, then press Left, Left, Left, Right, Right, Right, Left, A
Go to My Corner from the main menu, select record book, from there Most Wins-Boxer, and press Up twice to unlock him.
At the main menu select My Corner, then press Left, Left, Left, Right, Right, Right, Left, Right, Right