A strength-endurance index for power grip.

Area of Science:

• Biomechanics
• Occupational Health
• Ergonomics

Background:

• Muscle strength and endurance are critical for power grip tasks.
• Quantifying these parameters is essential for assessing functional capacity.

Purpose of the Study:

• To develop and validate a novel analyzer for quantifying muscle strength and endurance in power grip.
• To establish a simple method for graphing and scoring individual power grip performance.

Main Methods:

• A dynamometer test measured initial strength (IS) and final strength (FS) over 60 seconds.
• Endurance was calculated using the strength decrement index (SDI).
• A grip strength-endurance analyzer integrated IS and SDI data to generate a vector magnitude (Vmag) and strength-endurance performance scores (SEPS).

Main Results:

• Over 95% of participants scored within acceptable ranges for SDI, Vmag, and SEPS.
• Vmag was identified as the best predictor for SEPS, with a regression equation provided.
• The analyzer effectively identified individual scores outside acceptable ranges, including for injured efforts.

Conclusions:

• The developed power grip strength-endurance analyzer offers a straightforward method for visualizing individual performance.
• Converting strength and endurance data into SEPS provides a simplified metric for estimating overall power grip capacity.
• This tool aids in assessing grip performance deviations in both healthy and injured individuals.