Meeting Abstract

42.5  Thursday, Jan. 5  A mechanical basis for bilateral deficit and facilitation GUTMANN, Anne K.; University of Moscow, ID agutmann@uidaho.edu

Using two limbs, as opposed to one limb, to perform a task can affect single-limb performance. Both bilateral deficit (reduction of single-limb performance during bilateral tasks) and bilateral facilitation (enhancement of single-limb performance during bilateral tasks) have been observed for a number of tasks including simple, static tasks such as isometric hand grip exercises and complex, dynamic tasks such as jumping. Such differences in bilateral versus unilateral performance are commonly attributed to neural mechanisms – e.g. decreased or increased neural drive. However, in principle, mechanics alone can often explain such differences. Here I show how the mechanical requirements of a task and the mechanical capabilities of the limbs can interact to produce either bilateral deficit or bilateral facilitation. I also describe the general mechanical conditions that will produce bilateral deficit or bilateral facilitation and discuss how these results pertain to real-life examples.