During this time of the season, I will take a long hard look at my team.  You will have some running backs that will take the ball inside.  Adjust your offense to feed the ball inside for these backs.  You also now know that you have running backs that do not want to take the ball inside.  I have found that if I can get these backs outside, you will have more success.  Be careful with this.  Your outside backs must be willing to run the ball North and South.  Just because you have a player with great speed, it does not mean he is willing to turn up field with the ball.  If you find this to be a problem you must work you offense to help solve this problem.