45 Degree Back Extension: Form, Pad Height and 45 vs 90 Degree
How to do the 45 degree back extension: pad height, glute vs lower back versions, how it compares with the 90 degree bench, loading, sets and reps.
By Nadia Popescu, Strength & Conditioning Writer · Updated 25 October 2026
A rear delt row is a row where you flare your elbows out wide, to roughly 75 to 90 degrees from your body, and pull the weight towards your upper chest instead of your stomach. That change in elbow angle moves the work away from your lats and onto your rear deltoids and upper back. You can do it with dumbbells, a barbell, a cable or on a chest-supported bench, and it's one of the few rear delt moves that lets you use a decent load without your traps taking over. The catch is that it only works if you keep the weight moderate; go heavy and it quietly turns back into a normal row.
Your rear delts have one main job: pulling your upper arm backwards when it's raised out to the side, a movement called horizontal abduction. Picture the second half of a reverse fly and you've got it. A normal row, with tucked elbows, is mostly shoulder extension (your arm travelling back along your side), and the lats are the stronger muscle for that.
So the rear delt row is defined by three things, and they all depend on each other:
Grip matters a little too. A pronated (overhand) grip naturally encourages the wide elbow position. The opposite seems true for the reverse fly machine, where a neutral grip produced more posterior deltoid activity than an overhand one in a study of 19 trained men. For the row, use overhand to keep your elbows out, and save the neutral grip for your fly work.
This is the version to learn first. It's easy to set up at home and makes it obvious when your elbows start to drift.
You can also do it one arm at a time with your free hand and knee on a bench, which takes your lower back out of the equation. A single-arm dumbbell row setup works, but turn your elbow out and pull towards your shoulder instead of your hip.
The cue that fixes most rear delt rows
Think "elbows to the walls, not to the ceiling." If you imagine pushing your elbows out sideways towards the walls either side of you, your upper arms stay wide and your shoulder blades don't get dragged up into a shrug.
Lying face down on an incline bench is the cleanest way to do this exercise, and it suits most people best. With your chest on the pad, there's no hinge to hold, no lower back fatigue and far less chance of using momentum.
Set an adjustable bench to around 30 to 45 degrees, lie face down with your chest just over the top edge, and let the dumbbells hang straight down. Row with your elbows flared exactly as above. The full setup and the standard elbows-in version are covered in our chest-supported row guide; the rear delt version is the same position with a wider elbow path and lighter dumbbells.
There's some research support for fixing your position, too. A 2025 high-density EMG study on the seated row found greater posterior deltoid excitation during the pulling phase when the shoulder blades were held in a fixed position compared with letting them move freely. It was a small study of 14 trained men on the seated row, not a rear delt row, so treat it as a hint rather than proof. It does fit what most lifters feel: less body movement, more rear delt.
If you don't already have a bench that goes to an incline, a solid adjustable one is worth the floor space because you'll use it for presses, rows and flyes.
Check the FLYBIRD adjustable bench on AmazonThe barbell rear delt row uses a wide overhand grip, usually a hand or two outside your normal bench press grip. Hinge forwards, let the bar hang at arm's length, then row it towards your lower neck or upper chest with your elbows flared high and wide.
It's a good movement, but it's easy to abuse. Because a barbell is stable and you can load it in small jumps, people pile on weight, start yanking with their hips and end up doing a sloppy bent-over row with a wide grip. Keep your torso close to parallel with the floor, and if you have to stand more upright to move the bar, it's too heavy. A seal row bench or a chest-supported setup with a barbell solves the problem entirely if you have access to one.
Cables keep tension on the rear delts at the start of the rep, where dumbbells go slack. Set a cable station at chest height with a straight bar, a rope or two single handles. Sit or stand facing the stack, arms straight out in front, and row towards your face or upper chest with your elbows high and wide.
This looks very close to a face pull, and the two do overlap. The difference is mostly in the finish: a face pull adds external rotation at the end so your hands finish beside your ears, while a cable rear delt row keeps your forearms roughly parallel to the floor and stops when your upper arms are level with your torso. Single handles let each arm move independently and are often the most comfortable option.
Going too heavy and turning it into a lat row. This is the big one. As the weight climbs, your elbows creep back towards your sides and the pull drifts down towards your stomach, because your lats are far stronger than your rear delts. You'll still feel your back working, but it's no longer a rear delt row. Drop the weight until you can keep your elbows at shoulder height on every rep.
Shrugging. If your shoulders ride up towards your ears at the top, your upper traps have taken over. Keep your neck long and think about pulling your elbows out rather than up. A pause at the top will expose a shrug quickly.
Over-squeezing the shoulder blades. Some retraction is fine, but if you pinch your shoulder blades hard together on every rep, your mid-traps and rhomboids end up doing most of the work. Let the movement come from the upper arm moving around the shoulder joint.
Using your hips. In the bent-over versions, a little bounce from the hips gets a heavier weight up but removes tension from the rear delts. If you can't stop the body English, move to the chest-supported version.
Cutting the range short. Let the arms hang fully at the bottom. The stretched position is part of the work, and partial reps at the top are usually a sign the weight is too heavy.
The rear delts are small and recover quickly, so they handle frequent, moderate work well.
Add weight only when every rep of every set has your elbows level with your shoulders. On a pull day, slot it in after your heavy rows and pulldowns, when your lats are already tired. On an upper-body or push day, it fits at the end as a counterbalance to all the pressing. For a structured approach, our workouts hub has full splits you can drop it into.
These three moves all train the rear delts but in slightly different ways, so they complement each other rather than compete.
The rear delt row is your heavier option. Your mid-back helps a little, which means you can use more load and work the rear delts through a bent-arm path. The rear delt fly uses a long, straight-ish arm, so it's lighter but isolates the rear delts more directly and gives a stronger stretch. Face pulls add external rotation, which brings in the rotator cuff and makes them a favourite for shoulder health.
A simple weekly setup:
That's 6 or more hard sets a week aimed squarely at the rear delts, which is plenty for most people. For more options to rotate through, see our full list of rear delt exercises.
A normal row keeps your elbows close to your sides (or at around 30 to 45 degrees) and pulls towards your lower ribs or belly, so your lats and mid-back do most of the work. A rear delt row flares your elbows out to roughly 75 to 90 degrees from your torso and pulls towards your upper chest or neck line. That turns the movement into horizontal abduction of the upper arm, which is exactly what the rear delts do.
For most people, yes. Dumbbells let each arm find its own path and it's easier to keep the load light enough to feel the rear delts. The barbell rear delt row works too, but the fixed bar tempts you to load up and turn it into a heavy upper-back row. Use the barbell if you like it, just keep the weight honest.
Noticeably lighter than your normal row. A sensible starting point is around 50 to 60% of the weight you'd use for a standard dumbbell row for the same reps. If you can't pause for a second with your upper arms level with your shoulders, the weight is too heavy.
Work in the 10 to 20 rep range for 2 to 4 sets, two or three times a week. The rear delts are a small muscle that responds well to moderate loads, clean reps and plenty of weekly volume rather than heavy singles.
You can, but they work best together. The row lets you handle more weight with the help of your mid-back, the fly isolates the rear delts with a straight arm, and face pulls add external rotation for shoulder health. Pick one row and one fly or face pull variation per week and you've got the rear delts covered.
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