If you want to increase your upper-body strength and start seeing muscle definition in your arms, you've got to start doing upper-body workouts. Your arms aren't going to transform overnight or by doing an arm workout once in a blue moon.
To see more definition in your arms, implement this program into your routine at least two times a week and make sure you're selecting weights that will challenge you. If you're consistent with the program, you should begin to see results around the four- to six-week mark.
The workout: