Reported May 2005

A new gun design uses sensors to identify the owner.

WHAT DETERMINES THE STRENGTH OF SOMEONE'S GRIP? Many people assume that grip strength is primarily determined by the size of a person's forearm, particularly the wrists. But many other factors inside the hand really make a difference. The size, strength and structure of the hand -- including the palm and fingers -- all contribute to grip strength, and can vary widely.

Reflexes can also vary. For instance, how someone squeezes something can produce a unique pattern. The pattern can be detected by sensors, which read and record the size and force of a user's hand during the first second of squeezing.

There are several kinds of grip strength. A firm handshake, for example, is a form of crushing strength, while the ability to exert crushing strength on something and sustain it over time is an example of supporting grip strength. Pinch grip strength is the ability to grasp and lift an object between your thumb and fingers, and relies very heavily on the strength of the thumb.

Scientific studies disagree about what grip strength shows about a person's health. One study conducted by the Boston University Arthritis Center found that men with a strong grip were more likely to develop arthritis in certain joints of their hands and fingers. Another study conducted by the Honolulu Heart Program found that low grip strength could be an indicator for disability later in life.

If you would like more information, please contact:

Michael Recce, Ph.D.
Associate Professor of Information Systems
New Jersey Institute of Technology
(973) 596-5535

michael@ylem.njit.edu

Donald Sebastian, Ph.D.
New Jersey Institute of Technology
(973) 596-5535

Sheryl Weinstein
Media Liaison
(973) 596-3436

sheryl.m.weinstein@njit.edu

Did you know...

When applying for a job or meeting a prospective client, always use a firm handshake. A weak handshake indicates lack of confidence and indecisiveness.

The science of biometrics deals with ways to identify a person through the various unique biological markers, or "signatures," of the human body. The best-known methods are fingerprinting and iris and retina recognition, as well as voice recognition.