Following Proper form for Ab Roller
      
      
      Keep your arms stiff and straight. If your arms begin to tilt inward, you will be leading with your shoulders and thus the movement becomes a shoulder exercise instead of an ab exercise.
      
      
      
      
      
      
      
      
      Keep your arms stiff and straight. If your arms begin to tilt inward, you will be leading with your shoulders and thus the movement becomes a shoulder exercise instead of an ab exercise.