Rhomboids

back2 muscles

The rhomboids are two flat muscles between your spine and your shoulder blades that pull the shoulder blades together. They are hidden under the trapezius and are what a rowing movement is squeezing at the end.

The rhomboids are a pair of muscles on each side — rhomboid minor above, rhomboid major below — that run diagonally downward from the spine to the inner edge of the shoulder blade. They lie underneath the trapezius, so you cannot see them, but you can feel them working in the space between your shoulder blade and your spine.

They do one main thing: pull the shoulder blade in toward the spine. Because the fibres run at a downward angle from spine to scapula, they also pull it slightly upward and tip the shoulder socket to face lower — which is the detail that separates them from the middle trapezius sitting directly on top of them, which pulls straight across.

Grouping them as the rhomboids is gym vocabulary rather than an anatomical unit: they are two separate muscles with separate names and separate attachments, sharing one nerve, one direction of pull and a border so continuous that they are often indistinguishable in dissection. Since nothing you can do in a gym trains one without the other, treating them as one thing is the honest simplification.

This is the region people point to when they describe an ache between the shoulder blades, which is why the muscle name has spread far beyond people who lift. Whether that ache has anything to do with the rhomboids is a question for a professional.

Training notes

The rhomboids are trained by rowing, and specifically by the end of a row. Bringing the elbow behind the torso is arm and lat work; drawing the shoulder blades together after that is when the rhomboids do their part. A row that stops at the first of those has skipped them.

They respond best to the elbows travelling out and back at around forty-five degrees from the torso rather than tucked in against the ribs. Chest-supported rows, seated cable rows with a wide neutral grip, band pull-aparts and face pulls all put the work where it belongs and remove the lower-back fatigue that limits how much bent-over rowing anyone can usefully do.

This is one of the few muscle groups where a beginner will feel the difference from training it quickly, mostly because so little of ordinary life pulls the shoulder blades backward. Two to four sets of light retraction work a couple of times a week is a reasonable dose and does not need to be complicated.

Being underneath the trapezius means they can never be isolated, and no exercise claiming to isolate them does. That is fine: everything that trains the rhomboids trains the middle trapezius, and both were on the list anyway.

Muscles in this group

Exercises

Antagonists

Synergists