I did the cross-body arm swing for a week — and the results surprised me

a photo of a strong man in the gym stretching his arms
(Image credit: Shutterstock)

I’ve completed a lot of challenges for Tom’s Guide, some that threatened to break me at the beginning of a week (hi there, V-sit-up), some that caused little trouble because I was familiar with them (that’s you, my old friend, the triceps dip) and others that fell somewhere between the two. But when my editor, who’s not known for offering me the easy option, suggested I try cross-body arm swings for a week, my first thought was: “Is that as easy as it sounds?”. My second thought was: “This sounds like a trap.” But no, it’s exactly as it sounds. So what gives?

What is it?

The cross-body arm swing is usually billed as a warm-up move for those who are about to lift weights, and it is certainly that, because it warms up and loosens the muscles and tendons, and gets the heart rate up. But I also found it to be a terrific way to stretch my arm, upper back, shoulder and chest muscles, and it serves as a decent cardio move, too, depending on how many reps you do (or seconds, if you’re going by time). You can perform it anywhere, you don’t need any equipment, and you’re unlikely to bother anyone in the next room, as you won’t be breathing hard with the effort or dropping the best adjustable dumbbells dramatically on to the floor. There’s no excuse not to try this one.

How to do the cross-body arm swing

Here's how to master the move:

an illo of a woman doing the cross-body arm swing

(Image credit: Shutterstock)
  • Begin in a standing position, feet hip-width apart. Engage your core.
  • Raise your arms straight out to the side, at shoulder height, and with palms down.
  • Swing your arms past each other across your chest, allowing a slight natural bend in your elbow rather than keeping stiff arms.
  • Without stopping, swing your arms back as far as you comfortably can, ending at start position. (Imagine you’re trying to introduce your shoulder blades to each other.) As you do so, turn your palms so they’re facing up, to increase the stretch, and alternate which arm crosses over on top.
  • Aim for three sets of 30, or three sets of 30 seconds. Keep the movement fluid and maintain a straight back. Don’t allow the motion to convince your hips they have to rock bath and forth. That’s it. Easy.

Here’s what happened when I did the cross-body arm swing for a week

This is not one of those moves where I start off with poor form and gradually improve as the days go by. I started the week being able to do the move with no problem and I ended it the same way, though I had added reps with little effort. But I enjoyed it every day and could feel the benefits instantly.

Day 1 and 2

I started off with three sets of 30. The crunching and rumbling sounds coming from my upper back and shoulders told me this was a move my body had been quietly crying out for.  (Try this: roll your shoulders after a long period of sitting or first thing in the morning. That’s what I heard.) By the end of the exercise, my joints were moving smoothly and silently. I felt it in the top of my chest and my trapezius muscle, just below the back of my neck. It left me with the pleasing pull of a yoga move without the need to do a yoga move. On day two, I added five reps to each set. This is a lovely loosener after a few hours at the desk.

Day 3 and 4

As I added reps, I decided this was not just a warm-up move, but a traps workout. The trapezius muscle, which starts at the back of the neck and extends across the shoulder and partway down the back, is vital for good posture, as well as shoulder and neck movement. By this stage I was doing three sets of 40 reps, and noticed my arms waggling a little in the final few, as if trying pathetically to achieve lift-off. This requires more effort than you think, but I always felt good after the move. Go on, try it now: Stand up and do three sets of 20. See how it feels.

Day 5 and 6

There’s no getting away from the fact that this is an easy move and, therefore, many people will undervalue it, erroneously believing that if it’s easy, it can’t be doing much good. But I promise, add reps or seconds and you will feel the burn in your upper arms, upper back and chest. You will build strength and improve your range of motion.

Day 7

On the final day, I did the move standing on one leg (alternating between sets), to add something new. I was surprisingly steady — thanks, core exercises — and completed three sets of 50. It didn’t look terribly dignified, but I’ve done the fire hydrant exercise in a gym, so I know a little something about styling it out.

This move is simple, yes, but it’s does more than you might think and it’s a great way to break up a stint at a desk. In fact, I’m going to do it now, so I have to stop typing.

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John Carroll

John is a writer and editor based in London. He was worked for magazines such as Runner’s World, Men’s Health, Women’s Health and Cosmopolitan. A keen runner, what he lacks in ability he makes up for with enthusiasm and excuses.