There is a great diversity in those who play at the running back position. At one extreme are smaller, faster players. These fast, agile, and elusive running backs are often called "scat backs" because their low center of gravity and maneuverability allow them to dodge tacklers. Hall-of-famer Barry Sanders of the Detroit Lions and Chris Johnson exemplified this running style. "Scat backs" still active in the NFL include LeSean McCoy of the Tampa Bay Buccaneers, Tevin Coleman of the San Francisco 49ers, Christian McCaffrey of the Carolina Panthers and Alvin Kamara of the New Orleans Saints. This type of running back has grown in demand due to changes in offensive play calling, style, and tempo. The trending spread offense demands a player that can utilize open space as much as possible as run blockers are sacrificed to spread out the defense.