Dumbbell Chest Exercise Variations (KNOW THE DIFFERENCE!) If you flare your elbows out to about 60-70 degrees from your body while lying on a flat bench, you’ll place more emphasis on the middle fibers of your chest. If you keep your elbows tucked, you'll shift more of the workload to your triceps, reducing the focus on your chest. If you use an underhand grip, you will target more of the upper portion of your chest. If you hold one dumbbell with both hands and lower it above your head while kee