Psychophysical and psychosocial comparison of squat and stoop lifting by young females.

Psychophysical and psychological criteria are accepted risk measures for manual handling task assessment, yet few reports have compared squat and stoop using these criteria. Seventeen university students participated in a within-subjects cross over design study to compare squat and stoop techniques using maximum acceptable weight (MAW), perceptions of exertion (RPE), discomfort and preference. Mean (SD) MAW for squat was lower than for stoop (7.0 (2.2) kg vs 8.5 (2.4) kg) and RPE for squat was greater than for stoop (15.2 (1.5) kg vs 13.3(1.5) kg). More subjects reported discomfort following squat and a preference for stoop. The results provide limited support for use of stoop rather than squat technique for lifting a medium sized box from floor to knuckle height.