Effects of Gender,Lift Height,Direction,and Load on the Ability to Estimate Weight

Abstract

The study evaluated the effects of gender, lift height, direction (lift/lower), and load on the ability to correctly estimate weight handled. Seven women and six men lifted and lowered boxes to and from knuckle, waist, and shoulder heights. Subjects were asked to estimate weights corresponding to 50, 40, 30, and 20% of gender specific lifting strength to 152 cm. The difference between the actual and estimated weight (DIFF) was 100% greater for men than for women (F = 6.27, p = 0.03). When the percent difference was analyzed, there was no significant gender effect. The least accurate estimates occurred when lowering a weight from knuckle height (p < 0.05). The majority of subjects underestimated the weight and men underestimated more frequently than women (Chi² = 12.57, p = 0.0004). Subjects overestimated the weight more often at higher weights. The results suggest that both men and women tend to underestimate weight, especially when lowering from knuckle height, possibly putting them at risk for injury.

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