Data analysis
The average (and standard deviation) torque was obtained for each group of subjects in each of the six situations (two gripping techniques and three packagings). The condition of normality (Shapiro Wilk's W test) and homogeneity (Levene's test) of data were verified. In order to compare the average torque among the groups, ANOVA test was applied to normal and homogeneous data to compare both devices. Non-parametric tests were applied to the data sets that did not meet these conditions. All results were considered significant at a P value of 0.05 or less.