Lie on your side on an incline bench, bottom arm braced against the bench or hanging off the far side, dumbbell in your top hand resting against your thigh. Raise your arm up and slightly across your body until it's in line with your torso, leading with your elbow. Because gravity pulls straight down instead of straight out to your side, the hardest part of this raise is the top of the movement rather than the bottom, the opposite of a standing lateral raise. Lower slowly enough to feel the stretch before the next rep; the position makes it hard to cheat with your hips even if you wanted to.