The seated row primarily works the muscles between and around your shoulder blades: the rhomboids, middle trapezius, and latissimus dorsi. Your biceps, rear deltoids, and core muscles all contribute as secondary movers. The exercise is one of the most effective horizontal pulls for building back thickness, and the specific muscles it emphasizes shift depending on your grip and handle choice.
Primary Muscles: Mid-Back and Lats
The two biggest contributors during a seated row are the latissimus dorsi (the wide, fan-shaped muscles that span most of your back) and the rhomboids paired with the middle trapezius (the muscles that sit between your shoulder blades). An EMG study published in Dynamic Medicine measured muscle activation during seated rows and found that both the lats and the middle trapezius/rhomboid group fired at roughly 30% of their maximum voluntary contraction during a standard rep. Of all the exercises tested in that study, including lat pulldowns and reverse-grip pulldowns, the seated row produced the highest activation levels in the middle trapezius and rhomboids.
This is what makes the seated row a “back thickness” exercise. While vertical pulls like the lat pulldown emphasize the lats and build width (that V-taper look), horizontal pulls like the seated row load the muscles responsible for pulling your shoulder blades together. The result is a thicker, more developed mid-back.
Secondary Muscles and Stabilizers
Your biceps work throughout the entire pull. They flex the elbow to bring the handle toward your torso, and on heavier sets, they can easily become the limiting factor if your grip or form breaks down. One of the most common seated row mistakes is turning the movement into a bicep curl by pulling primarily with the arms instead of initiating the pull from the back.
The rear deltoids (the back portion of your shoulder muscles) also fire during the row, especially as you squeeze your shoulder blades together at the end of each rep. They assist with the horizontal pulling motion at the shoulder joint.
Below the surface, your core and spinal muscles do significant work. The erector spinae, the muscles running along both sides of your spine, contract isometrically to keep your torso upright and your lower back in a neutral arch. Your abdominals brace against the pulling force to prevent your spine from rounding forward. ACE Fitness recommends stiffening your abs throughout the movement while maintaining your natural lower back curve. Your hamstrings, glutes, and hip flexors also contribute as stabilizers, keeping your lower body anchored on the seat and foot pads.
How Grip Width Changes the Target
The muscles you emphasize during a seated row depend largely on where your elbows travel during the pull, and your grip width directly controls that. A close grip (like a V-bar handle) keeps your elbows pinned near your sides. This motion is called shoulder extension, and it biases the lats. A wide grip (like a long straight bar) flares your elbows outward. This motion is called shoulder horizontal extension, and it shifts the workload toward the upper and mid-back: the rhomboids, traps, and rear deltoids.
The crossover point sits at about 45 degrees of elbow flare from your body. At that angle, the shoulder moves through roughly equal parts extension and horizontal extension, meaning the lats and mid-back share the load evenly. Anything closer favors the lats. Anything wider favors the upper back. So if you’re trying to target a specific area, your grip width is the single most important variable to adjust.
It’s worth noting that the trapezius and rhomboids don’t actually cross the shoulder joint. They can’t directly pull your upper arm backward. Instead, they fire in response to scapular retraction, the act of squeezing your shoulder blades together. Any grip that encourages more shoulder blade movement will recruit these muscles more heavily.
How Grip Orientation Matters
Beyond width, whether your palms face down (pronated), face each other (neutral), or face up (supinated) also plays a role. The common advice is that an underhand or neutral grip targets the lats while an overhand grip shifts emphasis to the upper back. The mechanism is the same as grip width: palm orientation influences how your elbows track during the pull, which determines the type of shoulder movement. A supinated grip naturally tucks the elbows closer to your sides, favoring lat-dominant shoulder extension. A pronated grip encourages elbow flare, favoring upper-back-dominant horizontal extension.
In practice, the effect of grip orientation is smaller than the effect of grip width. If you keep your elbows tight to your body with an overhand grip, you’ll still hit your lats hard. The grip cues the movement pattern, but your actual elbow position is what matters.
V-Bar vs. Straight Bar
The most common handle choices are the close-grip V-bar and the wide straight bar, and they produce noticeably different training effects. The V-bar, with its narrow neutral grip, channels most of the work into the lats and mid-back. It also involves more bicep contribution because the neutral wrist position puts the biceps in a stronger pulling position. The straight bar with a wider overhand grip shifts focus to the upper back (traps, rhomboids, rear delts) and generally involves less total lat engagement.
Because the lats are a much larger muscle than the other back muscles involved, total load capacity tends to be higher with the V-bar. If your goal is overall back development, rotating between both handles over your training week covers more ground than sticking with one.
Squeezing Your Shoulder Blades: Does It Help?
A common coaching cue is to actively squeeze your shoulder blades together at the top of each rep. Interestingly, the EMG data tells a nuanced story. When researchers compared a standard seated row (allowing the shoulder blades to drift forward naturally at the start) to a version where lifters were coached to actively retract their scapulae, the middle trapezius and rhomboid activation was statistically similar between the two conditions. The lats showed a bump from about 30% to 37% of maximum contraction with the retraction cue, but the mid-back muscles didn’t change significantly.
This suggests the rhomboids and traps are already working hard during a normal seated row regardless of whether you consciously squeeze. The retraction cue isn’t useless, though. It can help prevent the common error of letting your shoulders round forward and turning the pull into an arm-dominant movement. Think of it as a form check rather than a muscle activation hack.
Complete Muscle Breakdown
- Latissimus dorsi: Primary mover, pulls your upper arms back toward your torso
- Rhomboids: Primary mover, pulls your shoulder blades together
- Middle trapezius: Primary mover, assists scapular retraction
- Rear deltoids: Secondary mover, assists horizontal pulling at the shoulder
- Biceps: Secondary mover, flexes the elbow throughout the pull
- Erector spinae: Stabilizer, holds your spine in a neutral position
- Abdominals: Stabilizer, braces against forward pulling forces
- Forearm flexors: Stabilizer, maintains grip on the handle
- Hamstrings and glutes: Stabilizer, anchors your lower body on the seat
The seated row is one of the few exercises that meaningfully loads nearly every muscle on the back side of your upper body while also demanding real core stability. Adjusting your grip width and handle type lets you steer that workload toward the lats or the mid-back depending on what your training needs.