LugNut Bat Weight - A Bat Weight Specifically Designed To Be Lighter To Reduce The Disruption Of Motor Patterning Required To Produce A Highly Consistent Swing. The issue caused by the use of heavy bat weights by youth players is that they alter the center of mass (COM) of the bat, which can disrupt swing timing, accuracy and swing mechanics. This is especially true for younger athletes who have not yet established the level of motor patterning required to produce a highly consistent swinging motion. Warming up in the on-deck circle with a HEAVY bat weight trying to emulate your natural swing motion is near impossible.