Dancing
Dancing is a very simple and traditional means of socially interacting, as well as a great way to just have fun. Science has recently shown that it can effect the hormone levels of both cortisol and testosterone, the stress and power hormones, and effect how attractive we find each other. It can also effect brain function, turn on the frontal lobes, and drive convergent or divergent thinking, depending on the type of dancing.
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安 Taming the Tiger, Waking the Possum 