Dynamic strength test as a predictor for maximal and acceptable lifting

Abstract

The aim of this study was to develop a practical and reliable test to predict the maximum lifting capacity of an individual. Dynamic strength during ‘isokinetic’ motion was measured on a device that allowed movement at either 0·73 or 0·97 ms⁻¹. For the ten men and ten women used as subjects, peak dynamic strength was compared with the maximum dynamic lift (MDL), the maximum load that an individual was able to lift once, from the floor to a shelf 113 cm high, without risk of injury. A step-wise multiple regression analysis indicated that the ‘isokinetic’ dynamic lifting strength (DLS) measured at 0·73 ms⁻¹ and sex accounted for 94·1% of the variance in MDL. The following equation was derived to predict MDL: MDL = 295 + 0·66 (DLS)− 148 (SEX), where DLS was measured in newtons, and SEX= 1 for men and 2 for women. Maximum acceptable load (MAL) selected for repetitive lifting at a frequency of six per minute was 22% of the MDL for both men and women. A simple test using a portable ‘isokinetic’ dynamic strength measuring device and involving one measurement was thus found to be a good predictor of maximum dynamic lift.

Additional information

Notes on contributors

JEAN LANDA PYTEL

Department of Engineering Science and Mechanics

ELIEZIER KAMON

Human Performance Research Laboratory