Rear Delts · Bodyweight
Arm Circles: The Warm-Up That Is Harder Than It Looks
Arms out at shoulder height, small circles growing into big ones, then the same again backwards. The rear delts hold both arms up the whole time, which is why 40 seconds burns.
Illustration adapted from Everkinetic via workout-guide, CC BY-SA 4.0. Full credits.
| Equipment | Bodyweight |
|---|---|
| Back zone | Rear Delts · Traps · Upper Back |
| Muscles | Rear Delts · Infraspinatus |
| Level | Beginner |
| Typical work | 2 × 30–40s |
| Where | Home or gym |
What is the Arm Circles?
Arm circles are a standing warm-up movement: arms straight out to the sides at shoulder height, drawing circles that start small and grow, run for 30 to 40 seconds in each direction. Holding two straight arms out horizontally is what makes it work, so the rear delts are under load for the entire set.
The one cue that matters: Small circles growing to big ones, both directions, shoulders down and away from your ears.
Why the Arm Circles is worth doing
- Two locked-out arms held at shoulder height is a long lever, so the rear delts are working from the first second with nothing in your hands
- Takes the shoulder through its whole circle in about a minute, which is the cheapest way to arrive at your first pull already moving
- Backward circles carry the hand behind the line of the body, the direction rows and pulldowns never send it
- Needs a metre of clear air and no kit, so it survives a hotel room, a busy gym floor and a session in the garage
How to do the Arm Circles
- Set the arms Stand tall with the feet about hip width, arms straight out to the sides at exactly shoulder height, palms down and elbows locked. Press both shoulders down away from your ears before the first circle.
- Start small Draw circles about the size of your fist for the first ten seconds. The hands barely travel; what is turning is the shoulder.
- Grow the circle Let the circles widen over the next twenty seconds until you are tracing the biggest one you can make with the shoulders still down and the hands still level with them.
- Reverse the circles Shrink back to small, stop, then run the same 30 to 40 seconds the other way. Backward circles take the hand further behind the body than forward ones, and that is the half most people skip.
- End on the line Finish the set the moment the hands drop below the height of your shoulders. Sagging arms mean the rear delts have stopped holding and momentum is drawing the circles.
Muscles worked
The Rear Delts (posterior deltoid) do two jobs at once here, which is why the set is not free. They hold a straight arm out horizontally for the whole clock, and they drive the back half of every circle as the hand passes behind the body. Work at that angle is what fills the shoulder out so it reads round and capped from behind, with a clear shadow line where the shoulder meets the back.
Infraspinatus (infraspinatus and teres minor) turns the upper arm outward as the hand climbs over the top of each circle. Palms down keeps the arm turned in and the work low on the shoulder; thumbs up rolls the arm open and shifts it toward the blade.
The shoulder blade has to rotate for the hand to get above shoulder height, a job split between the Upper Traps and the Lower Traps. When the upper fibres take it over, your shoulders climb toward your ears and the circle quietly shrinks. Shoulders held down means the lower fibres are doing their share of the rotating.
| <a href=”/back-muscles/rear-delts/”>Rear Delts</a> | Posterior deltoid — Rounded shoulders from behind — the detail that finishes a back. |
|---|---|
| <a href=”/back-muscles/infraspinatus/”>Infraspinatus</a> | Infraspinatus & teres minor — The plate under the shoulder blade. Separation, and healthy shoulders. |
Form tips
- Shoulder height is the standard. The arms sink as the set runs on, and every inch they drop takes load off the back of the shoulder. Watch one set in a mirror; most people are well below the line by the thirty-second mark.
- Locked elbows. A bent arm is a short arm and roughly halves the work. If the elbows start to soften, take smaller circles rather than folding them.
- Small first, big later. Circles that start big and cold are a swing. Beginning fist-sized and growing them means every position gets visited under control rather than thrown through.
- Equal time each way. Split the clock down the middle. Forward-only circles leave out the half where the hand travels behind you, and that is the half the rear delts are there for.
Common mistakes
- Shoulders climbing to the ears
- Once the shoulders bunch upward the upper traps run the movement and the circle shrinks without you noticing. Reset with the shoulders pressed down and start again from a smaller circle.
- Windmilling
- Fast circles thrown from the trunk turn this into a swing where momentum holds the arms up for you. Slow them down until you can feel the arm being held out at every point of the circle.
- Hands drifting in front of you
- Arms creeping forward of the body line hand the work to the front of the shoulder. Keep the hands in the plane of your shoulders or a few degrees behind it, which is where the back of the shoulder has to hold them.
- Treating it as a formality
- Ten seconds of loose flapping before a heavy set is a habit rather than a warm-up. Give it the full 30 to 40 seconds each direction and your arms will tell you it counted.
Sets, reps and where it fits
BackMaxx programs two sets of 30 to 40 seconds, and they go at the very front of the session, before the first pull of the day. Split each set between the two directions, take about thirty seconds between them, then go into your first working movement. It also fills the rest between sets of pressing, where nothing else is asking anything of the back of your shoulder.
There is no honest way to load this. Small plates in the hands turn it into a slow lateral raise and the side and front of the shoulder take over. Progress by holding the line instead: a full 40 seconds each direction, hands never dropping below shoulder height, shoulders never climbing. Once that is routine the movement has done its job, and the next step is loaded rear delt work such as reverse snow angels on the floor or banded face pulls for reps.
No bodyweight? Do this instead
There is nothing to substitute equipment-wise, since there is none. What sends people looking for a swap is space: a crowded rack area or a low ceiling makes a full circle impossible. Run one arm at a time with the other hand resting on an upright, which halves the width you need and lets you watch the working side. If even that is out, twenty slow banded face pulls with a light band cover the same tissue in the same minute. You gain resistance you can actually progress, and you lose the top half of the circle along with the freedom to do it anywhere.
Variations and similar exercises
- Reverse Snow Angel
- Runs a similar arc face down on the floor, where the weight of two straight arms makes it a working set rather than a warm-up. Pick it when the rear delts need training, not preparing.
- Cross-Body Shoulder Stretch
- Parks in one position and holds it instead of travelling through the circle. Better use of the last two minutes of a session than the first two.
- World’s Greatest Stretch
- Covers the hips, the upper back and the lats in one lunge, at the cost of more time and some floor. Choose it when everything in the session ahead is heavy.
Frequently asked questions
Do arm circles actually do anything?
Yes, though not the thing most people assume. Held straight out at shoulder height, each arm is a long lever, and the rear delts have to hold that lever up for the full 30 to 40 seconds while the shoulder travels through its whole circle. That is real work and a real warm-up. What it will not do is build the back of the shoulder, which takes load.
How long should you do arm circles for?
Thirty to forty seconds per direction, two sets, which is what BackMaxx programs as a warm-up. Split the clock evenly between forwards and backwards, and start each direction with small circles. Running past a minute each way turns the set into a burn test for the shoulders and stops it preparing you for anything, which was the point.
Are forward or backward arm circles better?
Backward, if you only have time for one. They carry the hand behind the line of the body, which is where the rear delts work hardest, while forward circles keep the arm in front and lean on the front of the shoulder. The honest answer is both, roughly half the clock each, since covering the whole circle is what the movement is for.
Should you hold weights during arm circles?
No. Even a light pair turns the movement into a slow lateral raise, the side and front of the shoulder take the work, and the circle shrinks to whatever you can control. Keep the hands empty, hold the arms at shoulder height for the full set, and put load into something built to carry it, such as a face pull.
Should the Arm Circles be in your plan?
BackMaxx scores your rear delts from one photo and builds the week around whatever is lagging — so the Arm Circles only shows up when it is the right call.
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