Scat backs vs. power backs, inside run vs. outside run

In football, there is a great diversity of running backs. Many of the most exciting players are the smaller and faster players, backs who use their speed and agility to elude defenders and make outside runs while dodging tacklers (Barry Sanders comes to mind). These are known as "scat backs." On the other extreme are bigger, stronger backs who are usually slower (but not always) than the smaller more agile scat backs. These are called "power backs."

In order to ascertain which backs are categorized to which type of running back and to what degree, I used the run direction data to look at running backs between the 2007-2009 seasons to roughly figure out which players were the "most extreme scat backs" and which were the "most extreme power backs" (but not necessarily the best or most successful). Here's what I came up with:





Although sorting the running backs by percentage of rushes they ran up the middle is simple enough, it produces names that match the characteristics for the running backs. However, it's curious to see guys like Brandon Jacobs and Jamal Lewis listed among the likes of Reggie Bush and Willie Parker, but when you see that Lewis runs toward the guards a high percentage of the time and rarely runs on the outside like the other scat backs, it looks like that his place in least used backs up the middle is dubious. For the power backs, Maurice Jones-Drew and Fred Taylor come out as the only running backs in the past three years to rush up the middle over 50% of the time, the most extreme power backs in the NFL today.

At the same time, the listings of Brandon Jacobs and the like as well as the absence of Adrian Peterson indicates that there is a third type of running back: the hybrid power-scat back. Here are the top 10 running backs with the lowest standard deviations of run direction (an admittedly quaint measurement to determine the best combo backs):



There's Purple Jesus. Looks like standard deviation may not be the best method to figure out which running backs represent a power-scat back inside-outside run distribution as Bradshaw, Bush, and Jacobs are listed in the top 3.

Anyway, looking at run directions for individual running backs definitely could use additional research. But what about run directions against certain defenses? Which defenses tend to allow the run up the middle and which ones on the outside?







Again, though this may look like interesting information, it looks like I'll have to do further research. For now, I'll leave the team defenses allowing runs up the middle vs. runs on the outside as is.