Destressing is an advanced stress management technique which rolls together the approaches of reducing, overcoming and releasing stress into a few seconds worth of time to provide a powerful 'reset' to the mind.
The simplest and single most effective cure for stress is taking a deep breath. The destressing technique is just an upgrade of this.
Destressing is like saying to your subconscious: "I'm experiencing this tension in response to a threat that no longer exists. I do not wish to experience it any longer. I ask for your assistance with destressing; I will step aside or provide full support so you can take care of this immediately. Thank you."
By working to integrate the conscious and subconscious mind (even for only a second) and giving the body a signal through taking a deep breath, wonders can be achieved. Of course, it takes practice.