In this video we look at a transition pad-work drill that concludes with one of the “nine karate throws” of Gichin Funakoshi (Byobudaoshi). The main purpose the drill though is the sequence before the throw.
When you watch the drill you’ll see that all three hand strikes are done with the same hand, but we have three different way of advancing and getting bodyweight behind the punch:
Hitting with the hand as we step forward (Junzuki / Oizuki).
Stepping so we deliver the punch with what is now the back hand (Gyakuzuki).