Since my blog about the double bounce, I have been asked a few times about my progression into this movement. Obviously, a lot has to do with each individual athlete and their mobility and training age, I will address the question as though all things are equal and we have an athlete that is mobile, motivated and cognizant of the goals for each lift. Time of year is another factor in the use of the double bounce.
When I first get an athlete, I prefer to use slow eccentric movements to help teach them proper mechanics. For the squat, using a 2-3 second eccentric portion of the lift will help the athlete develop proper motor control as well as aiding them on the "feel" of the lift.
As they progress through the weeks, using an isometric movement in the turnaround position can be the next phase. The athlete will slowly enter the bottom position, hold the position and then complete the concentric portion of the lift. The next step from the isometric movement would be to introduce a bounce out of the isometric move. The athlete controls the eccentric portion, pauses in the bottom position and then bounces out of the bottom position.
This will bring us to the double bounce. As they learn control in the previous movements, they will be ready to tackle the double bounce. Master the slow eccentric, the isometric movement, the isometric/bounce movement and finally the double bounce!! Now enjoy your leg strength gains.
At 1:32 you'll see the master of the double bounce killing a massive clean and jerk!!!