To her 1.4 million Instagram followers, Cassie "Badass Cass" Mason is known for her booty blasters, but her own favorite gym day is shoulder day.

If she's crunched for time, she'll superset shoulders and biceps, but in a perfect world, Cassie would be doing hours of strict shoulder routines balanced against her leg days.

For this workout, Cassie does six exercises, with 5 sets per exercise and 8-12 reps per set, going to failure on the last set of every exercise.

Within those 5 sets, she increases the weight 2-3 times.

Cassie Mason's Badass Shoulder Workout
Arnold press
5 sets, 8-12 reps
+ 6 more exercises


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Technique Tips

Arnold Press

The Arnold Press has a palms-inward start and progresses toward a palms-outward finish with the dumbbells, working the front of the delts, and the medial and posterior heads. This is a great exercise for a warm-up due to the shoulder rotation involved.

Upright Row

Mason does the upright row with a narrow grip on the EZ-bar, focusing on the traps and the anterior heads of the delt. A wide grip would be more focused on the lateral heads.

Upright Row

Side Lateral to Front Raise

Mason loves the side lateral to front raise because it works two areas of the delts, with overlapping work during the transition—similar to supersetting—in a great burnout exercise.

Pull-through Front Raise

Mason starts with her back bent at 45 degrees and her legs solidly planted at shoulder width. Then, she pulls the cables through her legs for a front delt burn.

Pull through Front Raise

Face Pull

Some people set the pulley at chest height for a face pull, but Mason sets it overhead for this trap isolation exercise, which also happens to hit the rotator cuffs and posterior delts for a great burnout or rehab round.

Rear Delt Cable Fly

With a bare-handed grab onto crossed cables, the rear delts are activated as the arms pull backward to a wide-open position. Mason pauses for a burn before returning to her starting position.

As with a lot of Cassie Mason's workouts, her rest periods on shoulder day are kept to a minimum to keep her heart rate up. We're talking 30-60 seconds. When she goes heavier, she rests longer—but not by much.

For more of her workouts, check her out on Instagram and YouTube.

About the Author

Contributing Writer

Jason Appelman’s authors consist of accredited coaches, doctors, dietitians and athletes across the world.

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