ROLE OF PHYSICAL WORK CAPACITY AND LOAD WEIGHT ON PSYCHOPHYSICAL LIFTRATINGS

This study examined the effect of load weight, and physical work capac ity (PWC) on psychophysical lift ratings of 33 men and 58 women. Each subject lifted seven boxes that ranged in weight from 6.8 kg to 40.9 k g and rated each lift with Borg's CR-10 scale. The lift components wer e a Vertical distance of the hands to the floor of 53 cm, and a vertic al lift distance of 48 cm. Subject PWC was assessed two ways: arm, sho ulder, torso, and leg isometric strength; and fat-free weight determin ed from skinfold fat, Physical work capacity was significantly correla ted with CR-10 ratings for each of the seven lifts and the women's rat ings were significantly higher than those of the men. Multiple regress ion showed that the CR-10 ratings were a function of lift weight and P WC (R = 0.87). Logistic regression quantified PWC levels for psychophy sically acceptable lift loads defined by CR-10 ratings less than or eq ual to 7. These results showed that lift load and PWC are independent factors of psychophysical lift ratings.