I did 50 Arnold presses a day for a week — here’s what happened to my shoulders

Woman performing an Arnold press
(Image credit: Shutterstock)

I decided to adopt the famous Arnold press every day for a week in a bid to sculpt a pair of shoulders even Arnie would be proud of, and feed my curiosity — could it make a difference to my shoulders?

But curiosity killed the cat, and this workout nearly killed me. The Arnold press has become a household name over the years, created by the bodybuilding legend himself, Arnold Schwarzenegger. His variation of the dumbbell overhead shoulder press has been widely adopted by keen CrossFitters, bodybuilders, and casual gym-goers alike in an attempt to build powerhouse shoulders like the man whose name is on the exercise label.

So why is it so popular? Unlike other shoulder exercises (this full-body dumbbell workout is a killer), the Arnold press works all three deltoids (shoulder) heads — frontal, lateral, and rear. The unusual but simple movement pattern recruits more frontal muscles simply by rotating your palms and works your muscles for longer so that you can build more for less.

Our fitness team has tested a fair few arm workouts between us — like the blogilates weightless arm workout — but 50 Arnold press a day? That’s a new one. If you’re looking for other ways to be fitness-creative, The Rock’s arm and ab workout is punishing, or read on to see what happened when I did 50 Arnold presses a day for a week.  

How to do an Arnold press  

Ilo of person doing an Arnold press

(Image credit: Shutterstock)

If you plan to diversify from the usual bench press, grab a pair of the best adjustable dumbbells and give this a go yourself: here’s how to do an Arnold press with proper form. 

It’s worth noting that you should always check with a health professional if you have a shoulder injury. I recommend performing this exercise seated against a bench — or kneeling — to reduce lower back pressure if your back niggles. And if you suffer from shoulder impingement (when the supporting rotator cuff muscles rub against the humerus arm bone), this exercise is sadly a no-go. 

How: Engage your core. Stand with your palms facing you and hold your weights in a bicep curl position close to your chest. From here, press the dumbbells above your head and rotate your palms to face outwards at the top. Then, simply reverse the steps back to your starting position. Done.  

Arnold press vs shoulder press 

Unlike the shoulder press, the Arnold press works all three parts of the deltoids, making it a bit of a champion shoulder all-rounder. The primary working muscles are:

  •  Anterior deltoids
  •  Lateral deltoids 
  •  Posterior deltoids 
  •  Triceps

A dumbbell overhead shoulder press primarily works the fronts of your shoulders and your chest, including: 

  •  Anterior deltoids 
  •  Lateral deltoids 
  •  Pectoralis major (your pecs) 
  •  Triceps

While the overhead shoulder press is better if you suffer from shoulder pain, it works less of the lateral and posterior shoulder heads. Regardless, both are killer compound shoulder exercises that work multiple muscle groups in one swift press. If you’re short on time, the Arnold press is your new best friend.  

Woman doing a seated Arnold press

(Image credit: Getty images)

I did 50 Arnold press a day for a week — here’s what happened to my shoulders 

 I decided to challenge my shoulder strength. Here’s what happened when I did 50 Arnold press a day, for a week.  

1. 50 reps felt like a lot of reps

I performed 5 sets of 10 reps at the same weight as my overhead press. Hypertrophy (building muscle) adopts 3-4 sets of 8-12 reps, so while the reps were at the top range, it wasn’t an outrageous number. 

Nevertheless, I rarely put this much work into isolating my shoulders, and I definitely went too heavy. Because your muscles work longer, the Arnold press is still hugely effective at a lower weight. Not only were my DOMs in full effect the following few days but pulling off my sports bra became a competitive sport.  

2. My shoulders feel stronger but look the same

By the end of the week, I could feel my body becoming more comfortable with the movement pattern and weight of the Arnold press, and I began to feel noticeably stronger — although I couldn’t physically see a difference. Of course, building muscle mass and strength is far more complex than meets the eye. 

Principles like progressive overload (gradually adapting variables like reps or weights), ample protein intake, managing your sleep hygiene and workout variety all play a role, but you can incrementally build muscle and strength week by week.

However, sculpting the shoulders of a goddess will partly involve losing body fat in conjunction with building muscle (learn how to calculate your body fat percentage and why it matters), and I wasn’t on a fat loss mission this time around. I won’t be entering a bodybuilding competition any time soon, but my overhead press has already improved. 

3. My workout became meditative

Getting through the first few days was the hardest. By the end of the week, I felt comfortable with both the rep, set and weight numbers, and the routine became meditative. I wouldn’t usually recommend my clients perform one exercise every day for high reps (unless they had a specific goal) because it can breed boredom and plateaus or lead to overuse and injury. 

However, it turns out Harvard (opens in new tab) has a name for it — muscular meditation. Moving your muscle groups repetitively and rhythmically can help to reduce stress, and because you are focused on your breathing, this can also help regulate the nervous system.  

4. I might have overworked my muscles

Research (opens in new tab)shows that your muscle ‘micro tears’ during exercise, which is why you experience muscle soreness the next day. Rest days and sleep are key times for muscles to repair and grow, so they must be allowed to recover.

Exercise variety and rest days are two ways to combat over-training to avoid strains and more serious injuries. With that in mind, maybe it’s time to give the Arnold press a rest. I wonder if Arnie pumped out 50 a day?

Next up: These are the 3 best dumbbell workouts for triceps and how to military press for strong shoulders military style. Also check out how I did 20 pike push-ups every day for a week — and what happened.

Sam Hopes
Staff Fitness Writer

Sam Hopes is a level III fitness trainer, level II reiki practitioner, and resident fitness writer at Future PLC, the publisher of Tom's Guide. Having trained to work with mind and body, Sam is a big advocate of using mindfulness techniques in sport and fitness, and their impact on performance. She’s also passionate about the fundamentals of training and building sustainable training methods.  When she's writing up her experiences with the latest fitness tech, you’ll find her writing about nutrition, sleep, recovery, and workouts.