Popsugar Fitness Workouts 100-Rep Arm Workout Get Strong, Defined Arms With This 100-Rep Arm Workout June 25, 2018 by Jenny Sugar View On One Page Photo 3 of 10 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 3 Overhead Triceps Extensions Stand with your feet hip-distance apart. Hold one dumbbell (go for your heavier weight) with both hands, bending the elbows behind your head. Straighten your arms to lift the dumbbell into the air, then slowly bend the arms to lower. This counts as one rep. Complete 10 reps. Previous Next Start Slideshow WorkoutsStrength Training10-Minute WorkoutsIntermediate WorkoutsArm Workouts