Rear Delt Exercises: The 6 That Work, and the Honest Reason Yours Don't
Rear delts decide how you look from behind and from the side. Six exercises that actually load them, plus the elbow-path fix for the trap takeover problem.
Someone sends you a photo from a party. It was taken from behind and slightly to the side, mid-conversation, and you have never seen yourself from that angle in your life.
Your shoulders look narrow. Rolled forward. There is a sort of collapse between your neck and your arms where there should be shape. And you have been benching three times a week for two years.
That angle is the one everybody else gets. And the muscle that fixes it is the one you have been doing three tired sets of at the end of back day, with weights that are far too heavy to work.
The short answer
The rear deltoid is the posterior head of the shoulder. It extends and horizontally abducts the arm — pulls your upper arm backward and out to the side — and assists external rotation. To train it: light to moderate load, 10 to 20 reps, a horizontal arm path, shoulder blades held still. The common failure is not the wrong exercise, it is letting the traps and rhomboids steal a movement the rear delt was supposed to do.
Key numbers
- Three heads. Anterior, lateral, posterior. Pressing hammers the anterior, lateral raises cover the lateral, and the posterior gets what is left — usually nothing. It runs from the spine of the scapula to the deltoid tuberosity, which is why it pulls the arm backward and outward rather than squeezing the shoulder blades.
- 10 to 20 sets per muscle per week is the working range most evidence-based coaches use for growth. For rear delts, spread it across two or three sessions.
- Roughly 75 to 90 degrees of arm abduction. Elbows away from the torso loads the rear delt; elbows tucked near 45 degrees hands it to your lats. This one angle is the difference between a rear delt exercise and a row.
- Ratios, not size. Singh's 1993 work established that body-shape preference tracks ratios rather than raw bulk — which is why the rear delt punches above its weight. It widens the numerator without touching the waist.
- 100 milliseconds. Willis and Todorov (2006) found first impressions of a face form in about a tenth of a second. Silhouettes are read at least that fast, from further away.
Why rear delts get missed — and the fix: the arm moves, the scapula doesn't
Nothing else in a normal programme trains them, and they sit where you cannot see them. A row involves the rear delt only as an assistant in a pattern dominated by much stronger muscles — so a four-day split can run eighteen months without once making the posterior deltoid the limiter in a set. And you check yourself head-on in a mirror, light in front: that view flatters the front delt and hides the rear one, while everyone else sees you from three-quarters and behind — the blind spot covered in how to pose for pictures.
Hence the sentence that fixes most people's training: you are not doing rear delts, you are doing a bad row. The rear delt moves your upper arm; your rhomboids and mid-traps move your shoulder blade. Those look nearly identical from outside, and if you initiate with the shoulder blade the rear delt spends the set as a passenger.
Three diagnostics for your next set:
- Where does your elbow travel? Out and back, perpendicular to your torso, stopping level with your shoulders. If it drives toward your hip pocket, you did a row.
- What moves first? If your shoulder blades pinch and your arms follow, that was scapular retraction. The arm leads; the squeeze is a consequence.
- What is tired afterwards? Burn between the shoulder blades or across the traps means the load went to the wrong address.
The fix is unglamorous: cut the weight in half. The rear delt is small with a long lever arm, so the load that makes it the limiter is genuinely light — lighter than your ego wants. Lead with the elbow, not the hand, and drop your shoulders away from your ears before every rep.
Caveat: some trap and rhomboid involvement is unavoidable and fine — they share the neighbourhood. The goal is not zero recruitment, it is making sure the rear delt fails first.
The six exercises
| Exercise | Why it earns a slot | The cue that makes it work | Most common error |
|---|---|---|---|
| 1. Chest-supported dumbbell raise (incline bench, 30–45°) | The default. Chest support removes all body English | Elbows soft and fixed; raise until the upper arms are level with your torso | Pulling the elbows back and down — that is a row |
| 2. Single-arm cable reverse fly (cross-body, mid pulley) | Constant tension through the path, more range than dumbbells | Handle across your chest, sweep out and slightly back | Rotating the torso to follow the arm — brace and stay square |
| 3. Rope face pull (high anchor, elbows above shoulders) | Rear delt plus external rotators; the best joint-health return here | Pull the rope apart, not to your face. End hands wide and high | Elbows dropping below shoulder height |
| 4. Machine reverse pec deck | Easiest to do correctly — fixed path, no stabilisation tax | Seat set so the handles are at shoulder height, then just move the arms | Seat too low, so you press down-and-back with lats |
| 5. Bent-over dumbbell reverse fly | Free-weight staple, works when you have nothing else | Hinge to near-parallel, flat back, arms sweep straight out | Standing too upright, which kills the load |
| 6. High-elbow row (to upper chest, elbows flared ~75°) | The one compound here that loads rear delts heavy | Pull to the sternum with elbows wide and high | Pulling to the navel with elbows tucked — a lat row |
Bonus: band pull-aparts — not a growth driver alone, but the cheapest way on earth to add frequency.
On grip: neutral or slightly pronated is the safe default. Pinkies up biases the posterior head slightly more, but the effect is small next to getting the elbow path right — and if a grip makes your shoulder pinch, it is not for you whatever it does on paper.
How to programme them so they actually grow
- Two to three sessions a week. Small muscle, fast recovery, low systemic cost.
- Two to four sets, 10 to 20 reps, close to failure. Growth happens across a wide load range when the set is genuinely hard, so use whatever keeps the rear delt as the limiter.
- Train them first, not last. The highest-impact change most people can make. After twenty sets of pulling your rear delts are cooked and your form has degraded to whatever gets the dumbbell up.
- Slow the lowering. Three seconds down — the fastest way to relearn what the muscle feels like loaded.
- Give it a month before judging. Shoulder width does not change in two weeks.
The missing axis
A silhouette is exactly what you cannot audit on yourself. You have never seen your own shoulders in motion from behind. Everyone else has.
Our free test reads that outside view — a 70–155 perceived-appeal reading with separate face, physique and styling components — so you can find out whether shoulder width is genuinely your bottleneck before you spend six months on it. Free, no paywall. If physique is your lowest component, body fat and first impression and the most attractive male body type follow on.
And the honest framing: shoulder width changes your outline, not your worth. Train it because you enjoy being strong and standing well, not because a photo from a party made you feel like less of a person. If the training becomes penance, it has stopped working.
The bottom line
Rear delts decide the two angles you never check and everyone else sees. Train them light, often, early in the session, in the 10 to 20 rep range. Lead with the elbow, keep the shoulder blades quiet, stop the arm level with your shoulders. Pick two of the six — a chest-supported or cable fly plus face pulls is the highest-return pair — twice a week for three months.
Meanwhile, shoulder seams and fabric weight change the outline immediately: how to dress well does in an afternoon what lifting does in a season. Do both. Take the free test first, so you know which to lead with.
Studies referenced
- Singh, D. (1993). Adaptive significance of female physical attractiveness: Role of waist-to-hip ratio. Journal of Personality and Social Psychology, 65(2), 293–307.
- Willis, J., & Todorov, A. (2006). First impressions: Making up your mind after a 100-ms exposure to a face. Psychological Science, 17(7), 592–598.
Frequently asked questions
What are the best rear delt exercises?
Chest-supported dumbbell rear delt raises, single-arm cable reverse flyes, rope face pulls, machine reverse flyes, bent-over reverse flyes, and high-elbow rows to the upper chest. The chest-supported and cable versions are the most reliable because they remove the momentum that lets your traps take over.
Why can't I feel my rear delts working?
Almost always because the weight is too heavy and your traps and rhomboids are doing the movement instead. The rear delt moves your arm. If your shoulder blades pinch first and your arms follow, you did a scapular exercise. Halve the load and slow the lowering to three seconds.
How often should I train rear delts?
Two to three sessions a week, two to four sets each, in the 10 to 20 rep range. The rear delt is small and recovers quickly, so frequency beats intensity here. Train it first in the session, not after twenty sets of pulling.
Do rear delts actually change how you look?
Yes, more per unit of work than almost any other small muscle, because they build the shoulder width you see from behind and from three-quarters — the angles you never check in the mirror and everyone else sees. See the most attractive male body type.