Using an overhand grip (palm facing away), hold a dumbbell in one hand and lie supine (on your back) on a flat bench.
Raise the dumbbell towards the ceiling so that you are holding it above your shoulder.
You may place your free hand under the elbow of your loaded arm for support.
Keeping your upper arm still, inhale as you slowly bend your elbow to lower the dumbbell to your opposite shoulder. Your elbow should be pointing out to the side.
Exhale as you straighten your elbow to lift the dumbbell back up to the starting position.
Repeat for the desired number of repetitions.
Repeat on the opposite arm.
Comments and tips
The lying one-arm cross-body dumbbell triceps exercise is a variation of the lying one-arm dumbbell triceps extension. The difference between the two is that in this exercise, the dumbbell is lowered to your opposite shoulder. This motion places your shoulder joint in an internally rotated position which may cause discomfort for some. If you feel any pain while performing the exercise, immediately stop.
Since this is a unilateral exercise, you can use it to target muscle imbalances between your arms.
Only the forearm should be moving. Keep the rest of your body still.
Lowering the dumbbell slowly will emphasize your triceps’ eccentric muscle contraction which may help with increasing muscle size.