A death grip is an extremely tight grip

Grip strength

Grip strength is the force applied by the hand to pull on or suspend from objects and is a specific part of hand strength. Optimum-sized objects permit the hand to wrap around a cylindrical shape with a diameter from one to three inches. Stair rails are an example of where shape and diameter are...

, such as that exerted by a person in a panic

Panic

Panic is a sudden sensation of fear which is so strong as to dominate or prevent reason and logical thinking, replacing it with overwhelming feelings of anxiety and frantic agitation consistent with an animalistic fight-or-flight reaction...

 for fear for their life. This was commonly thought to be a risk when rescuing a drowning

Drowning

Drowning is death from asphyxia due to suffocation caused by water entering the lungs and preventing the absorption of oxygen leading to cerebral hypoxia....

 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 practise and so breaking a death grip is no longer emphasised in lifesaving

Lifesaving

Lifesaving is the act involving rescue, resuscitation and first aid. It often refers to water safety and aquatic rescue however it could include ice rescue, flood and river rescue, swimming pool rescue and other emergency medical services. Lifesaving also refers to sport where lifesavers compete...

. The actual behaviour of a drowning person

Instinctive drowning response

The instinctive drowning response is a set of behaviors automatically undertaken by a person who either is, or is very close to, drowning.These are autonomic responses of the body, undertaken without deliberate control, and "represent a person's final attempts to avoid actual or perceived...

is more passive as they lack the oxygen to take violent action and an instinctive paddling reflex occurs.