When you're feeling down, you can breathe in a way that adds more breath energy, make the body lighter. When you're getting more manic, you can breathe in a way that makes the body heavier.

"I once had a student who was manic-depressive. She found that a large part of the problem was anticipating her ups and downs. The anticipation in and of itself would exacerbate the extremes. But she also found that in her extreme moods, the experience of the body was very different. This is where the breath became helpful. When she was feeling down, she could breathe in a way that would add more breath energy, make the body lighter, lighter, lighter, so she didn’t feel so weighed down all the time. And without the physical experience of being weighed down, her depressive mind states didn’t have so much to latch onto. This began to cut through the pattern. Similarly, when she found she was getting more manic, she could breathe in a way that made the body heavier. She would think a lot about the earth element, find whatever sensations in the body were solid, still, heavy, and substantial, and just focus on those sensations. That would balance things out. It would balance out the energy both in body and mind. So gradually the wild mood swings became a thing of the past. And her life wasn’t as dramatic as it was before, but it was a more reasonable life, a more manageable life."

~ Thanissaro Bhikkhu "Xtreme Drama"