Breathing in bodyflex is the most important aspect of it. If you breathe correctly, you’ll have better results. Bodyflex is based on the vacuum exercise. All of the exercises begin with this. In order to properly do it, follow this guide to perform the proper breathing cycle:

Stand in the pose which is shown in the picture: half-sided, legs apart from the body, tilted slightly forward. That pose is also called the “basketball player position”.
Free the lungs of any air. Exhale only with the mouth. Fold your lips as if pronouncing “oo”, then slowly exhale, trying to completely empty the lungs for the next breath.
Take a breath. An inhale in bodyflex should be taken only through the nose with the mouth closed. Try to inhale as deep as possible so that the lungs are full.
Take a sharp exhalation. Remember that the air is released through the mouth but at this stage, the lips are folded together. Quickly breathe out the air while making a “pahh” sound.
Hold your breath. When performing this part of the breathing exercise, your head should be lowered down and the stomach retracted. Count slowly. On the eighth count move on to the next point.
Pause. Stand in the initial position. Relax the muscles while breathing calmly through the nose.
Start the cycle over again.

I Did Bodyflex for 15 Minutes Every Day, and Here’s What Happened to My Body