SUPINACIÓN CONTRA PRONACIÓN: POTENCIAL DEL TORQUE

Supination versus Pronation Torque Potential 

As a group, the supinators produce about 25% greater isometric torque than the pronators 
(see Table 6-6). 
 This difference is partially explained by the fact that the supinator muscles possess about twice the physiologic cross-sectional area as the pronator muscles. 
 Many functional activities rely on the relative strength of supination. Consider the activity of using a screwdriver to tighten a screw. When performed by the right hand, a clockwise tightening motion is driven by a concentric contraction of the supinator muscles. The direction of the threads on a standard screw reflects the dominance in strength of the supinator muscles. Unfortunately for the lefthand dominant person, a clockwise rotation of the left forearm must be performed by the pronator muscles. Left-handed persons often use the right hand for this activity, explaining why so many are somewhat ambidextrous.

FUENTE: Neumann, Donald A., Kinesiology of the Musculoskeletal System , 2010