A death grip is an extremely tight grip, such as that exerted by a person in a panic for fear for their life. This was commonly thought to be a risk when rescuing a drowning person — that they would cling to their rescuer with a death grip which would cause them both to perish. Investigation showed that this did not actually happen in practice and so breaking a death grip is no longer emphasised in lifesaving. The actual behaviour of a drowning person is more passive as they lack the oxygen to take violent action and an instinctive paddling reflex occurs.
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Death grip Wikipedia(Text) CC BY-SA