Teres Major and Minor: Anatomy, Function and How to Train Back Width

The knot of muscle at the back edge of your armpit is the teres major. It runs from the lower shoulder blade to the upper arm bone and does the same job as your lats: it pulls the arm down and back. A good teres major exercise is therefore not a special move. It is a hard, well-loaded pulldown, pull-up or row.

That is the honest answer, and it is worth saying early because gym content often claims otherwise. This article sits inside our complete back training guide, and it covers what the muscle does, how it differs from teres minor, and what research can and cannot tell you about training it. For the wider map of lats, traps and erectors, see functional anatomy of the back muscles.

What is the teres major and where is it?

The teres major is a thick but flattened, rectangular muscle. It extends from the inferior posterior scapula (the lower, back surface of the shoulder blade) to the medial lip of the intertubercular groove of the humerus, a groove at the front of the upper arm bone (Syros and Rizzo, 2023).

In plain terms, it starts low on the shoulder blade and wraps forward to attach near where the lat tendon attaches. That is why you can feel it as a firm rope just beside the edge of the lat when you press your arm into your side.

What does the teres major do?

According to the same anatomy reference, it works synergistically with the latissimus dorsi to extend, adduct and internally rotate the humerus (Syros and Rizzo, 2023). Three words, three movements:

• Extension: swinging the arm backward, like the finish of a row.
• Adduction: pulling the arm in toward your body, like the bottom of a pulldown.
• Internal rotation: turning the arm so the thumb points inward.

This is the “upper lat synergist” idea. A synergist is a muscle that helps a prime mover do the same movement. The lats do the heavy lifting, and the teres major helps, from a position higher up and closer to the shoulder joint.

Teres major vs lats: what is actually different?

The lats are a big sheet reaching from the spine and pelvis to the arm. The teres major is a small muscle tied to the shoulder blade. Both pull the arm the same way. The practical consequence is that you cannot meaningfully split them with exercise choice. When the lats are loaded in a pulldown, the teres major is loaded too.

This is also why we do not buy the claim that one special grip or angle “hits the little lat.” Studies of pulling exercises mostly record the lats, not the teres major. The 2026 narrative review of 23 lat EMG studies, for example, concluded that an anterior bar path was the setup most consistently linked to higher lat EMG, that grip width effects were inconsistent, and that these were acute EMG readings rather than long-term training results (Di Fonza et al., 2026). Teres major was not the measured outcome.

We searched PubMed for studies measuring teres major activity during gym exercises and did not find one. So everything below about how to train it is reasoned from its anatomy and from lat research. That is a limit worth knowing.

Do wide-grip pulldowns hit the teres major more?

A popular belief says wide grips build width. The data on the lats do not support a big grip effect:

• In 15 men doing 6-rep-max pulldowns, narrow and medium grips allowed heavier loads than a wide grip, and lat, trapezius and infraspinatus EMG was similar across widths over the whole rep (the wide grip did show more lat activity in the lowering phase alone). The authors suggested similar hypertrophy should be expected with grips of 1 to 2 times the biacromial distance (shoulder-bone to shoulder-bone width) (Andersen et al., 2014).
• In 12 healthy men, a pronated (overhand) grip produced higher lat activity than a supinated (underhand) grip, whatever the width (Lusk et al., 2010).
• In 40 men with at least 5 years of lifting experience, seven pulldown variations differing in grip type, width and trunk lean showed no significant differences in lat EMG. Only the posterior deltoid differed, being higher with a wide pronated grip at 30 degrees of lean (Buonsenso et al., 2025).

Why might studies disagree with the gym folklore? EMG measures electrical activity in one short set, not muscle growth over months, and surface electrodes cannot easily pick out a small deep muscle like the teres major. None of these studies were about the teres major, and all were short-term with small samples of men.

A cautious takeaway: use an overhand grip, a width you can pull with a full range and a bar path that travels to your upper chest. For a deeper look at grip choices, read our breakdown of wide vs close vs neutral grip lat pulldowns.

Which exercises load the teres major?

Because its job matches the lats, the usual back staples cover it. Think in two arm paths.

Arms moving down (vertical pulls). Pulldowns and pull-ups. Lead with the elbows, not the hands, and bring the bar to your upper chest while keeping your ribcage stacked. We compare overhand and underhand options in pull-ups vs chin-ups.

Arms moving back (horizontal pulls). Seated cable rows and chest-supported rows. Drive the elbows back toward your hips and pause at the end. The narrative review above also reported that a narrower grip and a lower shoulder-abduction angle were each linked to higher lat amplitude in separate seated row studies, though they were not tested together (Di Fonza et al., 2026). Our guide to seated cable row attachments and elbow drive goes into detail.

Where does arm path matter? Elbow position decides how much of the load goes to the lats versus the mid-back, which we cover in lats vs upper back and elbow flare. It is a reasonable assumption that teres major follows the lats in these movements, but it remains an assumption.

Teres minor vs infraspinatus: the other “teres”

People mix up the two teres muscles all the time. They do different things.

Teres minor is a rotator cuff muscle. A 2018 review describes it as maintaining a balanced glenohumeral (shoulder) joint, and notes it becomes the most significant external rotator when major rotator cuff pathology is present (Williams et al., 2018). That is the reverse of teres major, which rotates the arm inward.

What about infraspinatus? It is a separate cuff muscle that also rotates the arm outward, but the two do not behave identically:

• In 18 collegiate baseball players, teres minor activity was higher than infraspinatus during resisted horizontal abduction, and lower during resisted external rotation. Both rose when the arm was held at 45 degrees of external rotation (Tsuruike and Ellenbecker, 2022).
• In 10 healthy people measured with intramuscular electrodes, side-lying external rotation gave the highest teres minor activity, about 67% of maximum voluntary contraction, among seven rotation exercises. That study was a rehab-oriented, single-group design (Reinold et al., 2004).

So the practical split is simple. Pulls grow the lats and teres major. Light rotation and rear-delt work look after the cuff, including teres minor and infraspinatus. We cover the cuff side in rotator cuff strengthening for shoulder health and rear delt training.

How to program it: a simple template

You do not need a teres major day. Fold it into your normal back work.

Goal	Movement	Sets and reps	Note
Vertical pull	Pulldown or pull-up, overhand	2-3 x 8-12	Elbows down, bar to upper chest
Horizontal pull	Seated or chest-supported row	2-3 x 8-12	Elbows toward hips, brief pause
Cuff health	Light external rotation or face pull	1-2 x 12-20	Easy weight, no pain

A rough weekly target of 10-16 hard sets of back work suits many people, and you can move toward the lower or higher end by how recovery feels. That figure is a common coaching range rather than a number measured for teres major. Stop most sets with 1-3 reps in reserve, and add reps before you add weight. Our RIR and RPE calculator helps with effort, and the free pull day plan has a ready-made layout.

Common mistakes with upper back width work

• Chasing a “teres major exercise” that does not exist. Spending sets on odd angles instead of progressing pulldowns and rows.
• Letting the grip decide everything. Width matters less than whether you can complete a full range under control.
• Ignoring the cuff. If you only pull heavy, light rotation work keeps the small muscles around the joint worked too.
• Skipping the stretch at the top. A controlled full stretch between reps is part of the movement.
• Confusing shoulder pain with a tight muscle. Pain is a signal, not a cue to push harder.

If you want to see a hard pulling movement that loads the lats in a long, stretched position, try the dumbbell pullover, but note that the narrative review found the pullover appeared to preferentially load the pecs rather than selectively target the lats (Di Fonza et al., 2026).

Can the teres major get injured, and when to see a doctor

Injuries to the lats and teres major are rare. A review of case reports found they are seen in a range of sports, disproportionately in the throwing shoulder of baseball pitchers, and that isolated teres major injuries are generally treated without surgery (Donohue et al., 2017). That review also notes there is no standard of care, and it rests on case reports, which are the weakest kind of evidence.

For an ordinary lifter, the lesson is to warm up, add load gradually and avoid yanking the weight. See a doctor or physiotherapist if you notice:

• a sudden sharp pain or a pop under the armpit or at the back of the shoulder
• visible bruising or swelling in the area
• weakness lifting or rotating your arm that does not settle within a few days
• shoulder pain at night or numbness and tingling down the arm

We cannot diagnose from an article, and these signs need an in-person assessment.

Indian lifter notes

You do not need fancy equipment for this. A lat pulldown machine and a seated row station in a basic gym cover everything above. If you train at home, assisted or band pull-ups and a door-anchored band row load the same pattern at lower cost. For fuel, 1.6-2.2 g of protein per kg of body weight is a typical range for lifters, and dal, paneer, curd, soya chunks and eggs get most vegetarians there. Use the protein calculator for your own number.

The bottom line

The teres major is a real, distinct muscle that helps the lats pull the arm down and back. It will grow along with your lats if you train pulldowns, pull-ups and rows hard and progress them over time. No study we found shows a grip or exercise that targets it alone, and grip width has weak support as a lever in the lat studies we do have. Teres minor is a different muscle with the opposite job, so look after it with light rotation work instead.

Pick two vertical and two horizontal pulling movements, log your reps and add a little each week. For the complete plan, return to the complete back training guide.