Still kneeling, he gazed up at Ro, who felt her legs and shoulders tensing in an involuntary fight-or-flight reaction.

Me, I was trying to avoid going into a fight-or-flight reaction.

She'd been expecting the call, since he was returning hers, but even so, it tripped her fight-or-flight reactions.

Catecholamines help the body respond to stress or fright and prepare the body for "fight-or-flight" reactions.

Eyes that now fed a message to his brain it plainly did not wish to accept, given the fight-or-flight reactions that brain was producing.

Stress triggers a hormonal fight-or-flight reaction that speeds up the heart and quickens breathing.

Acute stress is a "fight-or-flight" reaction to an immediate threat.

Chronic stress requires you to suppress your natural "fight-or-flight" reaction over hours, days, or even years.

What Collins underwent at 10:26 is called a "fight-or-flight" reaction: a surge of blood pressure, adrenaline and energy to prime the muscles for action.

In humans, though, the link between the fight-or-flight reaction and heart disease hasn't been so easy to demonstrate.