Physiological Evaluation of the Effectiveness of Six Different Back Belts

Abstract

Back belts lately have generated considerable debate as to their effectiveness. Eight male subjects wore six different back belts (wide and narrow, firm and flexible) while squat and stoop lifting a tote box at two loads, 15% MVC and 40% MVC. Four different physiological measures were recorded: 1) erector spinae EMG, 2) ratings of perceived exertion, 3) blood pressure and heart rate, and 4) low back compressive forces (Fcomp). A no-belt control condition was also tested. A general linear model revealed no significant differences in any of the physiological measures for either the type of belt or no belt used (p>0.05). However, load and posture showed significant (p<0.05) effects. Also, the body mass index (BMI) was a significant covariate, with higher ratings, blood pressure, heart rate and Fcompfor higher BMI. Overall, the results of this study add to the growing body of evidence that back belts may not offer a reduction in the physical stress associated with manual materials handling.