The Split jump is technique which has to be mastered by a badminton player right from the beginner level, so that it gets straight into one mind.
Every professional player does this every time but, goes unnoticed as he wraps the footwork skills into this jump. his split jump is usually made at the center of the court after every player return a reply and comes to the center and does a split jump and then only readies himself for the next possible opponents return. This whole action phrase is completed in milliseconds, that goes un-noticed by audiences, but well felt by the player himself.
The split jump is called by many names viz., split step, bounce start. They all refer to this same footwork. Usually this Split Jump is made for a quick start towards the direction of the shuttle, so that the player reaches the shuttle early and has time to reply his best to his opponent.
The timing for this split jump is split second and you are start movind towards the direction of the shuttle for the best reply.
The important thing to understand is that must not wait. Your pushing off movement should immediately follow your split jump. Otherwise, the feel of the split jump and your quick movement towards the shuttle is lost.