Instant Relaxation
This is a breathing exercise / visualization that can immediately calm you, slow down your breathing and help you drop stress. You can do it for only a breath or two, or for as long as you like. (Don't do this while driving, folks! LOL

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The Sponge
Imagine you are a sponge, lying in a pool of warm water.
Imagine yourself bobbing at the surface, gently supported by the water.
Imagine the pores of your body are like pores of The Sponge.
As you breathe in, feel yourself drawing in this warm water through every pore in your body.
As you breathe out, feel the water soaking into your whole body. Soon the water bathes each cell in warmth.
As the water soaks into your body, you begin to feel heavy and your weight sinks down.
Each time you breathe in, you are drawing in more of this warm water through your pores.
Each time you breathe out, the water is soaking into your bones, your muscles, your cells, until your whole body is warm and heavy.
If you want me to talk you through it, here's a link:
http://www.audioyoga.com/sponge.htm
There's an audio track on there that starts with some nice gentle music and then I talk you through this visualization. Enjoy!