Why do we shake when we’re nervous or frightened?

Asked by: Sarah Gordon, Coventry

When we’re anxious, a region of the brain called the amygdala responds to the threat by increasing the production of adrenaline, the ‘fight-or-flight’ hormone. Adrenaline works directly on receptor cells in muscles to speed up the contraction rate of the fibres, ready for fighting or fleeing.

High levels of adrenaline can therefore lead to muscles twitching uncontrollably, making us shake. Deep, ‘box’ breathing (in for a count of 4, hold for 4, out for 4) can help to calm us down again.

Read more:

• Why do you feel sick when you’re nervous?
• Can dogs smell fear?

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