Empty-Can is an important rotator cuff exercise because it strengthens the supraspinatus muscle, the muscle of the rotator-cuff group that is most often injured in sports. This exercise is named for the position used to empty a can. All rotator cuff exercises consist of movements that must be performed with perfect form to ensure that the proper muscles are being isolated.
It must be stressed again that all rotator cuff exercises performed with dumbbells must be performed with light weights (2-3 pounds); using heavy weights will strengthen the larger muscle groups more (deltoids, lats) resulting in a possible muscular imbalance.
Empty-Can Exercise Guide
STARTING POSITION (SETUP): Stand upright with your feet about hip-width apart and hold a dumbbell in each hand.
EXERCISE EXECUTION (MOVEMENT): Keeping your arms straight, raise your arms to shoulder height creating a V-shape, move them horizontally about 30 degrees, and rotate* them inwardly as much as possible so that the palms are facing the floor. Slowly lower and raise the weights through a 45-degree arc. It should look as if you are emptying liquid from two cans— that’s how the exercise got its name.
* You can rotate your arms internally/inwardly (as if you were pouring out a can) before raising them (this can be your starting position), during the movement or even when your arms are already raised to shoulder height (recommended).
Empty-Can Additional Tips & Key Points
- Lift the dumbbells until your arms reach just past parallel with the floor.
- Lift your arm at a 30-45-degree angle between forward and sideways, and turn your thumb downward at the same time, like you’re turning a can upside down.
- Full-Can Exercise. The EMG activity of the supraspinatus in the Empty-Can (thumbs down) vs. the Full-Can (thumbs up) is the same. The difference lies in the activity of the deltoid. The Empty-Can produces high levels of activity in the middle deltoid when compared to the Full-Can.
This excess amount of deltoid activation in comparison with the supraspinatus activity leads to superior humeral head migration and a decrease in subacromial space. The position of the scapula also can produce subacromial impingement. The present research supports the use of the FC as the recommended exercise for strengthening the supraspinatus and maximizing the subacromial space.