"It's physiological and it's emotional." "Physiologically,we have a tendency when we come into a situation that seems dangerous we get a lot of chemicals flowing through our bodies to help us stay alert, to be able to act if we need to act.

VOA: standard.2010.07.01

It's one of the pillars of healthy life, psychologically, physiologically.

它是健康人生的支柱之一，不论是心理上还是身体上。

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