Considerations of Physiological Design Parameters for Dynamometers
Purpose: This paper considers the relevance of grip strength in everyday life and why and how it is measured to establish a baseline of physiological design parameters which will allow the development of a standardised test protocol for the handgrip dynamometer which generates consistent and accurate results.
Methods: Relevant publications were reviewed and evaluated to glean insight into the effects of various device and test parameters on the test outcomes.
Results: A number of physiological parameters were consistently reported as having a negative effect on the reliability of the test results. These parameters include variations in the: Choice of test Device, Anthropometrics, Test Protocols, Body Position, Instructions, Device Feedback, in addition to a range of Physical parameters which will be discussed in a subsequent review.
Conclusions: Even though Jamar controls a majority of the hand grip testing market, there are a range of results as well as a range of Jamar products available on the market which give a variety of test results. These test results, in combination with inconsistencies identified in the above listed test parameters, revealed inconsistent medical examination outcomes. It is possible to develop a standardized testing protocol and to incorporate appropriate physiological considerations to generate a more standardised outcome from hand grip tests.Many devices have been made available on the market with widely varying applications due, in part, to an inconsistency in understanding of physics and the inconsistent selection of design parameters.
Grip strength is important for everyday activities in and out of the work environment. The assessment of explosive and sustained grip strength is used as an indicator of overall strength and health as well as to measure the impact of injuries to the hand and wrist.
A reliable device is required to run grip strength tests. The device must be of a design appropriate for use by normal healthy individuals as well as patients with hand deformity, tissue sensitivity and reduced ability who can only deliver low levels of force. It must also be able to deliver results that are both accurate and reproducible.
Keywords: Dynamometer, Grip Strength, Jamar, Test protocol, Hand Grip Strength Testing