Popsugar Health & Fitness Workouts Best Exercises to Build Muscle in Your Arms Transform Your Upper Body With These 18 Strengthening Exercises 6 July 2018 by Tamara Pridgett View On One Page Photo 6 of 18 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 6 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. Previous Next Start Slideshow Fitness TipsBack ExercisesArm ExercisesStrength TrainingWorkouts