The relationship between maximum pull force and the coefficient of friction (shown in mean ± SE). Mean friction coefficient = 0.40 for cotton glove-aluminum, 0.61 for cotton glove-rubber, 0.72 for PVC dot glove-aluminum, 0.78 for bare hand-aluminum, 0.80 for PVC dot glove-rubber, 1.10 for bare hand-rubber. (Pull and extended elbow posture only.)