The efficiency of a lever depends upon the relative length of power arm and weight arm. These principles particularly apply in draft work to the question of lowsetness. The weight of the load is a direct force that corresponds to something pulling back on the animal. As stated above, the longer the power arm the greater the advantage, hence the longer the limb of the horse the greater the advantage that the load will have over the animal. The teamster consequently requires that his draft horse be lowset, in order to gain a greater efficiency.